Party 7

Party 7 is a 2000 Japanese surreal comedy film written and directed by Katsuhito Ishii. The film features an ensemble cast including Masatoshi Nagase, Keisuke Horibe, Akemi Kobayashi, Yoshinori Okada, Yoshio Harada, Tadanobu Asano, and Tatsuya Gasyuin. The film follows two voyeurs who watch a Japanese gangster and his bizarre guests in a hotel room.

Synopsis from Wikipedia, CC BY-SA 4.0. Everything below written here.

Poster © the film's rights holders.