ICN · SEOUL KIX · OSAKA

Osaka Winter Dossier

A from-scratch plan for 6 friends — flights and accommodation both booked for Jan 6–12, 2027, now expanded to a full Osaka ⇄ Tokyo ⇄ Mt Fuji loop on overnight buses plus a rental car for the Fuji leg, with halal food + solat built into the schedule, and a full per-person cost breakdown.

Party

6 friends

Length

6 nights · 7 days

Dates

Jan 6–12, 2027

Per person

≈₩947k

Is Osaka even the right call?

Fair question — you asked from scratch, so it's worth answering honestly instead of assuming. I weighed it against the two other realistic winter picks from Korea: Fukuoka (the shortest hop) and Hokkaido (the only one with actual snow).

Note: the table below is the original Osaka-only comparison from when this dossier started. The plan has since grown to include Tokyo + Mt Fuji (§07) — see §05 for the current, up-to-date budget.

Destination	Winter flight, r/t	What you get	≈ Per person, 4N5D
Osaka / Kansai this plan	₩230k–320k	Castle, old-town Kyoto, Nara's deer, Dotonbori food crawl, USJ — the most "bucket list" density per yen, plus two easy day trips.	₩800k–950k
Fukuoka	₩200k–300k	Shortest flight of the three (~1h). Food- and onsen-led — Dazaifu, Yufuin/Beppu hot springs — quieter, but far fewer headline sights.	₩800k–1.1M
Hokkaido / Sapporo	₩500k–800k	The only one with real snow — skiing, the Snow Festival, proper winter cold. Genuinely a different trip, not a variant of the same one.	₩1.3M–1.8M+

💭 My honest take: stick with Osaka. Given "cheaper is better" has been the brief the whole way through, it's genuinely the best value of the three — cheapest flights, and Kyoto + Nara give you more range than Fukuoka's day trips for similar or less money. Fukuoka's only real edge is an even shorter flight — worth it only if you'd rather eat and soak than sightsee. Hokkaido is the one honest upgrade: it's real winter, snow included, which Osaka's 5–12°C simply isn't. But budget roughly doubles, and the Snow Festival itself runs Feb 4–11, 2027 — right on top of Seollal, so you'd be stacking two price surges at once. If a "real winter" trip is the actual goal, that's worth planning as its own trip later with a bigger budget, not squeezed into this one.

Booked ✓ — Jan 6–12, 2027

Ticket's in: Peach Aviation MM712, ICN → KIX confirmed. That's 6 nights / 7 days — two nights longer than the 4N5D this dossier was built around, so the itinerary and budget below now stretch to match.

Outbound

Wed 6 Jan · ICN → KIX

07:30 → 09:15

1h 45m. Lands mid-morning — you'll realistically be through immigration, bags, and on the Nankai Rapi:t to Namba by ~10:30–11:00.

Return

Tue 12 Jan · KIX → ICN

07:40 → 09:45

A genuinely early flight — check-in for LCCs usually closes ~40–50 min before departure, so you need to be airside by ~6:00–6:20am.

📌 One honest note: Jan 6 is a day earlier than the "wait for the post-holiday crash" window I'd flagged (fares tend to properly settle from Jan 7). Not a problem now that it's booked — just means you likely paid a touch more than the rock-bottom Jan 12+ rate. Nothing to do about it at this point, and it's still miles better than a Dec 20–24 departure would've been.

⚠️ The 07:40 return is the one thing to plan around. Namba to KIX is ~45 min by Nankai Rapi:t, but the first train of the day usually doesn't run early enough to make a 6am airport arrival comfortably. Check the actual first-train time closer to the date — if it's too late, either take a late-night/overnight option, book an airport-area hotel for the last night instead of Namba, or pre-book a taxi. Don't leave this to the morning of.

Getting there — flights

ICN → KIX is one of the most heavily served short-haul routes out of Korea, so the LCCs undercut the flag carriers by a wide margin. Book roughly 6–8 weeks out on a weekday for the fares below.

Carrier	Type	Round trip / person
T'way Air	LCC	₩230,000–290,000 cheapest
Jeju Air	LCC	₩240,000–300,000
Air Busan / Jin Air	LCC	₩250,000–320,000
Korean Air / Asiana	Full service	₩380,000–480,000

Compare across all of these at once on Naver Flight, Skyscanner or Trip.com rather than one airline's own site — LCC seat sales don't always show up until you filter by date.

Also worth checking — flying out of Gimpo (GMP) instead

Gimpo does run a Kansai route: Korean Air, Asiana and Jeju Air each fly it twice daily, plus Peach four times daily — about 14 departures a day combined, same ~1h45m flight. Off-peak, with an airline coupon, fares can dip into the high ₩100,000s per person — in the same ballpark as the Incheon LCCs above.

The real draw isn't the ticket price, it's the airport itself: Gimpo sits inside the city, ~20–30 min from most of Seoul, versus 60–90 min out to Incheon. For a group of 6 that's a real chunk of time and transfer cost saved, especially on an early flight straight after your last paper.

The trade-off — T'way, the cheapest carrier in the table above, doesn't fly this route, and departure times cluster mid-morning to evening rather than spreading out, so there's less room to chase an ultra-cheap red-eye.

🧭 My take: if any of you actually live near Gimpo or central Seoul, check Jeju Air / Peach on GMP–KIX before booking — the time and transfer money saved can outweigh a slightly higher fare. Purely on ticket price alone, though, Incheon still has the edge, since it has more carriers fighting for your seat.

Where to sleep

Both stays booked and paid ✓ — a 6-person guesthouse room in Nishinari Ward, Osaka (8.7/10, 229 reviews) and a 2-night apartment in Bunkyo, Tokyo (8.2/10, 237 reviews). Here's what that means in practice, plus what the Namba hotel options would have cost as comparison.

What you booked

nippori — Nishiten Bunka Mansion, 3-7-3 Tachibana, Nishinari Ward, Osaka 557-0051. 1 room, 6 adults, Jan 6–12.

Settled at ₩52,000 per person for the whole 6-night stay — the ₩95,216 shown on the listing was the room's headline nightly rate, not what you actually owed; your share came to a lot less than that. Combined with the flight, you've paid ₩356,000 per person total — meaning the flight itself worked out to roughly ₩304,000. Both are settled, so these are locked numbers now, not estimates.

🔍 Still worth a message to the host (via Contact — usually replies in ~4hrs): confirm "1 room, 6 adults" means 6 actual sleeping spots (futons/bunks), not 6 guests squeezed into a room built for fewer. The listing photo shown was 1 of 10 and looked like a smaller room — ask for photos of the specific setup you're getting, so nobody's surprised on the night of Jan 6.

Tokyo — what you booked

9STAY Bunkyo Otsuka — an apartment stay opened in 2025, 8.2/10 over 237 reviews, in Ōtsuka, Bunkyo Ward. 330 m from Shin-otsuka (Marunouchi line), ~1 km from JR Ōtsuka (Yamanote line, ~10 min to Shinjuku). Fri 8 → Sun 10 Jan, 2 nights, self check-in after 15:00, check-out before 10:00.

Paid ₩249,969 for all 6, so ₩41,662 each. It's non-refundable and can't be modified, so these dates are now fixed. It replaces the manga cafe and the night in the car: a real bed and a bathtub between the overnight bus and the Fuji drive.

🔍 Message the property before the trip: (1) can you leave bags before 15:00 on Fri 8 Jan? (2) is there a kitchen? (3) is there any parking nearby for a minivan on Sat night? The booking number lives in the group chat, not here.

📍 On the location — Nishinari Ward, honestly: this is Osaka's budget-guesthouse district, and it's a mixed bag by block. The part with a rough reputation (Airin/Kamagasaki, around Dobutsuen-mae and Shin-Imamiya stations — day-labourer history, public drinking, "Triangle Park") is real but localised; other pockets (Tamade, Kishinosato, Tengachaya) are quiet and residential. I can't place 3-7-3 Tachibana precisely against that without a map in front of me, so pull up the walking route from your nearest station to the guesthouse yourselves and see if it skirts that core area — and check the property's own recent reviews for any comments on the neighbourhood at night. Transit itself is genuinely good: ~10 min by train to Namba or Tennoji. Practical rule regardless: stick to main, well-lit streets after dark, and travel the block between station and door as a group, especially the first night when nobody knows the route yet.

For reference, here's what staying in Namba/Dotonbori proper would have cost instead — useful if any of the above gives you second thoughts and you want a fallback:

Best value

Sotetsu Grande Fresa Namba

₩100k–150k / night, twin

Tight to Dotonbori canal, no-frills rooms, free amenity bar in the lobby.

Best amenities

Dormy Inn Premium Namba

₩150k–200k / night, twin

Public bath (great after a cold day out) and a free late-night ramen service.

Most space

Cross Hotel Osaka

₩200k–250k / night, twin

27m² rooms — worth it if you'd rather spread out than save the last ₩50k.

What it costs — per person

Updated for the final route: Osaka ⇄ Tokyo ⇄ Kawaguchiko (Mt Fuji) on overnight buses instead of shinkansen plus a 2-day rental car for Fuji, an Osaka Amazing Pass day, 2 nights in a Tokyo apartment, and halal food costed separately since "whatever's cheapest" doesn't apply the same way when half the conbini shelf is off the table. Full minute-by-minute version with these same numbers is in the Excel file.

Line item

₩ / person

Round-trip flightPeach MM712 — paid ✓

304,000

Guesthouse6 nights, 1 room ÷ 6 — paid ✓

52,000

Intercity + local transportOvernight buses Osaka↔Tokyo both ways, rental car to Fuji (÷6), Osaka↔Kyoto return, KIX transfers, city metro

196,920

Osaka Amazing Pass1-day — metro + Castle + Umeda Sky + Tsutenkaku

31,500

Tokyo apartment9STAY Bunkyo Otsuka, 2 nights, ₩249,969 ÷ 6 — paid ✓

41,662

Food — masak sendiriBreakfasts and dinners at the guesthouse, kitchen confirmed ✓

16,200

Food — makan luar (halal)Day 1 (before check-in), every meal in Tokyo, Kawaguchiko lunch + dinner, Day 6 lunch in Kyoto

186,300

Optional attractionsShibuya Sky (¥2,700) + Kiyomizu-dera (¥500) — skip freely if trimming

28,800

Shopping & buffer

90,000

Total / person

947,382

Flight + both stays are locked at ₩397,662/person, paid. The two overnight buses still double as two nights' accommodation, which is how 6 nights stay this cheap. Skip the optional attractions line and this drops to ≈₩918,582/person.

Total for all 6

₩5.68M ≈ $4,110

Kereta sewa — yes, for the Fuji leg

The plan: rent a 7–8 seater in Tokyo on Saturday morning, drive to Kawaguchiko for the day, drive back to the Tokyo apartment that night, and return the car on Sunday morning. It's a round trip from Tokyo, so there's no one-way drop-off fee, which is what killed the car idea before. It costs a little more than the bus, but you get the lakes and Oshino Hakkai on your own schedule.

Who drives

Three of the group have Malaysian licences and take turns. Each driver must show passport + original Malaysian licence + Malaysian IDP (JPJ, RM150, the 1949 Geneva booklet) at the counter. No IDP, no car. From Korea, apply in the MyJPJ app (needs MyDigital ID), have it couriered to family in Malaysia, then posted to Korea. That takes weeks, so start now. The licence must still be valid for at least a year when you apply.

What it costs (Toyota Rent a Car, W2 class: Noah / Voxy)

Rental, Sat 08:00 → Sun ~10:30 (~26 h)	≈¥35,000
Winter tyres (needed Dec–Mar)	¥3,300 / 24 h
Insurance (damage + NOC cover)	≈¥4,000–5,000
Chuo Expressway tolls, round trip (ETC)	≈¥5,200
Fuel + parking (incl. Sat night in Tokyo)	≈¥8,500
Per person (÷ 6)	≈¥10,000 (≈₩90,000)

⚠️ The drive back is at night. You leave Kawaguchiko around 18:30 after Isyak, in the dark, at below-zero temperatures, so roads can have black ice. Swap drivers every hour or so, stop at Dangozaka SA if anyone is drowsy, and don't push on tired. The apartment has no parking: book a coin park or an akippa spot near Ōtsuka for Saturday night (≈¥2,000–3,000) before the trip.

❄️ Winter driving + a 3-day weekend. Roads around Fuji can be icy, so drive gently and keep a long gap. 9–11 Jan is a long weekend, so the Chuo Expressway out of Tokyo on Saturday morning will be busy. Malaysia drives on the left like Japan, which helps.

✅ Compared with the bus plan: the Shinjuku → Kawaguchiko bus and the Fujiyama Liner drop out; the car and a Sunday-night Tokyo → Osaka Willer bus come in. The car costs about the same per person as the two buses it replaces.

The route — Osaka ⇄ Tokyo ⇄ Mt Fuji, 6 nights 7 days

Osaka first, an overnight bus up to Tokyo and two nights in an apartment there, a rental-car day trip out to Kawaguchiko for Fuji, a Sunday in Tokyo, and an overnight bus down to Osaka, skipping the shinkansen entirely. A full Kyoto/Nara/USJ day didn't fit without cutting Tokyo or Fuji short, so Kyoto gets a half-day on Day 6 for Kiyomizu-dera. Full airport-to-airport schedule with exact times, every meal and every solat slot is in the companion Excel file — this is the condensed version.

Wed 6 Jan — Land 09:15, full day in Namba

Confirmed flight lands 09:15am — a whole day, not just an evening. Immigration + bags, Nankai Airport Express to Namba (¥970, ~45min — regular express, not Rapi:t). Kuromon Market for lunch, guesthouse check-in from ~2pm, unhurried Shinsaibashi/Namba afternoon, then Dotonbori at night — Glico sign, canal, a kushikatsu crawl. Halal lunch + dinner near Namba since the guesthouse kitchen isn't in play until you're checked in.

Thu 7 Jan — Osaka + Amazing Pass, bus out to Tokyo overnight

Cook breakfast at the guesthouse (kitchen confirmed). Buy the 1-day Osaka Amazing Pass (¥3,500) and use it for Osaka Castle, then Umeda Sky Building before 3pm — free entry cuts off then — then Tsutenkaku/Shinsekai for dinner. Pack up, and at 23:00 board the overnight bus to Tokyo (Willer Express, ¥2,000–4,000, ~8–9h, sleep on the bus). Solat note: Subuh (05:38) and Isyak (18:20) both land while you're still out sightseeing — plan around Zohor/Asar at the castle park or a quiet corner near Umeda.

Fri 8 Jan — Arrive Tokyo, explore

Bus lands Shinjuku ~07:30. Freshen up at the terminal, halal breakfast (onigiri/bread), then Asakusa Senso-ji (free). It's Friday: leave Asakusa ~11:30 for Tokyo Camii in Yoyogi-Uehara (~40min, Ginza → Chiyoda line) for Solat Jumaat — azan ~12:30, prayer ~13:00, khutbah in Japanese, Turkish and English. Lunch after, at the mosque's halal market or in Shin-Okubo. Collect the bags from the Busta Shinjuku lockers and check in at 9STAY Bunkyo Otsuka from 15:00 (JR to Ōtsuka, ~10 min): shower, rest, Maghrib. Then Shibuya Crossing and Harajuku after dark, Isyak at the Shibuya PARCO prayer room, halal dinner, and an early night. Heads up: Subuh (~05:22) falls while the bus is still moving — pray seated with a qiblat app, or qada on arrival if you genuinely can't.

Sat 9 Jan — Rental car day trip to Mt Fuji

JR from Ōtsuka to Shinjuku (~10 min) and pick up the car at Toyota Rent a Car Shinjuku at 08:00 (passport + licence + IDP for all 3 drivers). Chuo Expressway to Kawaguchiko IC: ~1h30m if clear, expect 2h+ since it's the start of a 3-day weekend. Chureito Pagoda first while Fuji is clear, hoto lunch at T&T Fujiyama Halal, Zohor at Fujikawaguchiko Masjid, then Oishi Park and Oshino Hakkai. Maghrib with the sunset, dinner and Isyak at the masjid's halal café, then drive back to Tokyo at ~18:30 and park near the apartment for the night. Night drive: dark, below zero, possible black ice. Swap drivers every hour; rest at Dangozaka SA if anyone is drowsy. Overnight parking near the apartment needs booking (§06).

Sun 10 Jan — Return the car, Tokyo day, night bus to Osaka

Check out by 10:00 with the bags in the car, drive to Shinjuku, refuel and return the car ~10:30. Bags into a coin locker at Busta Shinjuku. Akihabara late morning, Zohor at Masjid Nusantara, lunch at Halal Wagyu Karemen King, then over to Shibuya: Asar at the PARCO prayer room and Shibuya Sky on a 14:45 slot (¥2,700 online, optional, the first thing to cut if trimming). Maghrib, halal dinner, then the 23:00 Willer night bus from Busta Shinjuku to Osaka (~¥3,000–5,000; book early, it's a holiday weekend). Solat: Zohor at Masjid Nusantara (Akihabara); Asar and Maghrib at the Shibuya PARCO 5F prayer room.

Mon 11 Jan — Rest, then half-day Kyoto: Kiyomizu-dera

The night bus arrives ~07:00–09:00; head back to the guesthouse to shower, nap and cook breakfast. Leave ~10:30: Midosuji Line Namba → Yodoyabashi (¥240), then Keihan Line → Kiyomizu-Gojo (¥430), ~1h15m total. Zohor + halal lunch at Shinjuku-tei Kiyomizu near Ninenzaka (halal wagyu ramen, with a prayer space; opens 12:00; chicken paitan ¥1,500–2,500, wagyu ramen ¥4,500). Walk up Ninenzaka/Sannenzaka to Kiyomizu-dera (¥500, cash, open 06:00–18:00), Asar nearby, then head back ~15:30 so you're in Namba by Maghrib. Cook dinner with the leftover groceries and pack early — tomorrow's flight is brutal. Heads up: Jan 11, 2027 is a Japanese public holiday (Coming of Age Day), so expect Kyoto to be busier than a normal Monday. The last stretch from Kiyomizu-Gojo is a steep ~25-minute uphill walk; if the group is wiped after two overnight buses, a taxi split six ways is cheap. Skipping Kyoto and just resting is still a fine call.

Tue 12 Jan — Fly out, 07:40

Up ~04:30, Nankai Airport Express Namba → KIX ~05:00 (¥970, ~45min). Airside with buffer for check-in and immigration well before 07:10 boarding. Sleeping at the airport the night before instead is an option if Day 6 runs late or you'd rather skip the early commute — but since the guesthouse night is already paid, using it and doing the 45-min transfer is the better value call.

Halal food, solat & masak sendiri

Prayer times and halal access shift the plan in ways generic "cheap Japan trip" advice doesn't cover, so this is its own section rather than a footnote.

Waktu	Osaka/Kansai	Tokyo/Kawaguchiko
Subuh	~05:38	~05:22
Zohor	~12:00	~11:47
Asar	~14:35	~14:20
Maghrib	~17:00	~16:45
Isyak	~18:20	~18:05

Estimated from NAOJ sunrise/sunset data for early January — close enough to plan around, but confirm with a prayer app (Muslim Pro / IslamicFinder) once you land.

⚠️ The overnight buses are the real challenge. Both of them (Osaka→Tokyo on Day 2, Tokyo→Osaka on Day 5) cross a Subuh window while still moving. Bring water/tayammum-safe wipes, a qiblat app, and don't be afraid to pray seated or to jamak/qada once you land if it genuinely isn't possible on board.

Where the halal food actually is

Osaka: Gyomu Super has several halal-stocked branches (Nippombashi, Minamitsumori, Bentencho, Momodani) — meat, rice, spices, snacks; Halal Ramen Naniwaya near Namba does bento from ¥1,200 and a wagyu rice bowl around ¥3,000.

Tokyo: Tokyo Camii (Yoyogi-Uehara) is a full mosque with a halal market and Turkish food attached — the plan for Friday Jumaat on Day 3. Shin-Okubo also has a cluster of halal-friendly Turkish/Middle Eastern spots.

Kawaguchiko: better than it used to be. Fujikawaguchiko Masjid (opened 2020) has a halal café in the same building; T&T Fujiyama Halal Restaurant does halal hoto near Chureito; Idaten Bettei by the station is halal with a prayer room. Still carry a backup snack, since small places fill up on weekends.

🍳 On "masak je supaya jimat": honest answer — cooking only realistically works on the Osaka guesthouse nights (Day 2 and Day 6, kitchen confirmed). Days 3–5 you're out all day in Tokyo or on the road (ask 9STAY whether the apartment has a kitchen; if it does, breakfasts there are a bonus), so those meals are mostly eat-out regardless of intent. Budget-wise that's roughly 40% cooked, 60% bought — still worth doing (₩16,200/person in groceries instead of eating out for those same meals), just don't expect it to cover the whole week.

Book these now — before seats/slots run out

Most of this trip is walk-up (temples, markets, Dotonbori). A handful of things aren't — they're either capacity-limited (a bus has a fixed number of seats) or timed-entry (a ticket for a specific hour). Miss the window on these and you're either stuck, or paying a lot more for a same-day scramble. Here's the honest priority order.

Priority 1 — book this week

The two overnight buses (Willer Express Osaka→Tokyo, Thu 7 Jan; Tokyo→Osaka, Sun 10 Jan), the rental car, and the drivers' IDPs

These aren't optional add-ons — they're your transport and your accommodation for those nights. If either sells out, you're not just missing a fun extra, you're stuck rebuilding the whole route (extra hotel night, more expensive shinkansen, knock-on schedule changes for everyone).

Japan highway bus operators typically open bookings around 3 months before departure — for a Jan 6–12 trip, that window is opening right about now (late Sept/early Oct). Two things stack risk on top of that: Jan 6–12 sits right at the tail end of Japan's New Year travel rush (many locals are still moving around through the first week of Jan, and Japanese school winter break often runs into early/mid-Jan), and Sun 10 Jan is the middle of a 3-day weekend, so both Tokyo→Osaka bus seats and 7–8 seater rental cars get tight.

Rental car: book a W2-class (Noah/Voxy) with winter tyres and an ETC card, Sat 9 Jan 08:00 → Sun 10 Jan ~11:00 in Shinjuku. IDPs: the 3 drivers need their Malaysian IDP booklets in hand before the trip. From Korea that means MyJPJ, a courier to Malaysia and then post, which takes weeks, so start this now.

✅ Worth it? Not really a question — these ARE the plan, not an optional extra. Book via willer-travel.com (English site, card payment) as soon as your headcount and dates are locked. Book all 6 seats in one go if the site allows it, so you're guaranteed to sit together.

Priority 2 — book 1–2 weeks ahead

Shibuya Sky (Day 5, listed as optional)

It's a timed-entry ticket, not a walk-up queue — you book a specific hour through the official site. Current pricing: ¥2,700 (~₩24,300) online before 3pm, ¥3,400 (~₩30,600) from 3pm onward, +¥300 more if you buy at the counter instead of online (assuming there's anything left to buy). Sunset slots sell out first, but in January sunset (~16:45) lands right on Maghrib, and they're the pricier after-3pm tier, so the plan uses a 14:45 slot instead. Tickets release 14 days ahead at midnight (Korea and Japan share a time zone), which is 27 Dec for the Sunday (Day 5) visit.

💭 Worth it? Yes, if it survives the budget trim — 360° open-air Tokyo view with Fuji visible on a clear winter day is genuinely one of the better skyline views in the city, better than most indoor observation decks for the same price bracket. If you're doing it, book the 14:45 slot online as soon as tickets release on 27 Dec, not the morning of. If it gets cut for budget, no regrets — it's correctly flagged as the first thing to drop in §05.

Priority 3 — optional, consider adding

teamLab Planets or Borderless (not currently in the itinerary)

Two separate venues now: teamLab Planets (Toyosu — barefoot, walk-through water rooms, structured route) and teamLab Borderless (Azabudai Hills — shoes-on, open wander, no fixed path). Dynamic pricing from about ¥3,600 (~₩32,400) per adult, rising on busy days. Planets tickets are never sold at the door — online only, always. Borderless sometimes has same-day counter tickets if inventory's left, at a small surcharge. January is off-peak compared to sakura/Golden Week/summer, so sellout risk is lower than the "book weeks ahead" warnings you'll see online, but weekend slots (your Day 4, a Saturday) still go first.

🧭 Worth it? If anyone in the group hasn't done a teamLab before, it's a genuinely different kind of attraction — immersive digital art, very photogenic, not "just another museum." The honest catch: it's not currently budgeted, and Day 5 only has room for one big timed-entry thing alongside everything else planned. If it replaces Shibuya Sky rather than stacking on top, it's a wash on both time and cost — worth a group vote on which one people actually want more.

Done ✓ — no longer needed

Manga cafe booths, Tokyo (replaced by the 9STAY apartment)

Individual booths rarely "sell out" city-wide, but a specific branch can run short on private/group booths on a Friday or Saturday night in a busy area like Shinjuku or Shibuya — exactly your Day 3/4 nights. Most chains (Gran Cyber Cafe, Media Cafe Popeye, Manboo) let you reserve online or by phone.

💭 Worth it? Reserve the branch and booth type (flat-mat rooms fit a group better than single reclining seats) a few days ahead rather than the same day — low effort, removes a real "where do we sleep tonight" risk for 6 people arriving off an overnight bus.

Everything else in the itinerary — Osaka Castle, Kuromon Market, Dotonbori, Asakusa, Tokyo Camii, the Kawaguchiko Fuji viewpoints — is free or walk-up, no booking risk. The Osaka Amazing Pass (§05) is sold at machines/stations same-day and doesn't sell out.

Ways to trim it further

Fly Tue/Wed/Thu. Weekend departures from ICN run noticeably higher on every LCC — shifting either leg by a day can save ₩20,000–40,000 a head.

Skip the rail pass entirely. With Tokyo↔Osaka now running on overnight buses instead of shinkansen (§05/§07), a JR pass wouldn't pay for itself — a rechargeable ICOCA/Suica for city metro is all you need on top of the bus tickets.

Conbini breakfast on the days you must eat out. Halal-safe picks (salmon/tuna onigiri, bread) run ¥600–800 versus ¥1,500+ for a sit-down café — over the Tokyo/travel mornings for 6 people that's a real line item, not a rounding error.

Confirm the room before you pay, not after. A single "sleeps 6" listing is how you got this price — message the host for photos of the actual bedding setup so nobody's finding out about the floor situation at midnight on Jan 6.