Urusei Yatsura

Season 3

Episode 21: Operation: Peek in the Woman's Bath

Ataru takes a bath at an old-fashioned sento (along with Cherry), where he tries to peek on the girls' side, where Lum, Shinobu, Sakura, Ran, Ryoko, Ryunosuke, Benten, and Oyuki are having a private party. But soon the Stormtroopers and even Mendou find out about Ataru's plan.