Soak in the Infinity Castle and the Wisteria House
The event, officially titled Demon Slayer × Yunessun Hakone Onsen Tan: Fuji no Hana no Kyūsoku (roughly, "Hakone Hot Spring Tale: Rest of the Wisteria Flowers"), transforms the swimsuit-friendly pools at Hakone Kowakien Yunessun into locations from the anime. A press release from resort operator Fujita Kanko detailed three headline attractions.
The "Wisteria Flower Bath" fills the park's indoor Green Terrace area with wisteria decorations and Demon Slayer Corps imagery, evoking the Wisteria Family Crest Houses that shelter demon slayers in the series. The bath is scented with wisteria flower fragrance.
Outside, the "Infinity Castle Bath" takes over the Rock Cave Onsen area. It recreates the battle between Tanjirō Kamado, Water Hashira Giyū Tomioka, and Upper-Rank Three Akaza from the Infinity Castle movie, with immersive set design. The scent here: watermelon.
There's also a "Wisteria Flower Steam Bath" sauna in the outdoor Finnish Bath area. Staff run löyly and aufguss (steam-pouring and towel-fanning) sessions twice daily at 11:30 AM and 2:30 PM, themed as "special training" with Sound Hashira Tengen Uzui and Flame Hashira Kyōjurō Rengoku watching over the proceedings. All three attractions are included with standard Yunessun water-area admission (from ¥2,500 for adults, ¥1,400 for children age 3 and up).
Exclusive ufotable Art and the First Demon Slayer Hotel Room
For the event, animation studio ufotable produced original illustrations of five characters enjoying Hakone in yukata: Tanjirō, Zenitsu, Kanao, Giyū, and Shinobu. These illustrations appear on exclusive merchandise bundled with limited collab tickets (adults from ¥2,800, children from ¥1,900, tax included), with an original face towel as a bonus. Tickets went on sale June 10.
The adjacent Hakone Hotel Kowakien, which opened in July 2023, is offering its first anime collaboration room. The Demon Slayer Room features interior decorations drawn from anime and film scenes, with only one room available per night. Rates start at ¥52,500 per person (before tax, double occupancy), including two meals and unlimited access to Yunessun and the Mori no Yu bath area. Guests receive a novelty set: a hand towel, fan, mesh bag, and acrylic marker charm.
A more affordable accommodation plan offers an original tenugui (traditional cloth hand towel) for the first 500 guests, starting at ¥28,500 per person. Room and accommodation reservations opened June 11.
Looking Ahead
The event opens July 18, 2026, exactly one year after the Infinity Castle Chapter 1 theatrical premiere and just 11 days before the film's Blu-ray and DVD release on July 29. The movie earned over ¥40 billion at the Japanese box office (approximately $730 million worldwide across 158 territories), so Demon Slayer's commercial pull remains enormous heading into this summer run.
Yunessun is located in Hakone, a major hot spring resort town in Kanagawa Prefecture about 90 minutes from central Tokyo by train. The park operates as a swimsuit-required facility, making it accessible for families and mixed groups. Full event details and ticket links are available on the official event page.
No international ticketing or English-language booking option has been announced. Visitors will need to book through Fujita Kanko's Japanese reservation site. The Demon Slayer anime, based on Koyoharu Gotouge's manga (220 million copies in print via Shueisha's Jump Comics), is streaming globally on Crunchyroll and Netflix. A full rebroadcast of the TV anime series has been airing in Japan since April 5, 2026.