Deathmatch! Ataru VS Mendo Brigade! Urusei Yatsura : Season 1 Episode 129

Episode 2 of a 2-episode serial. Despite their best efforts, all of Lum's Stroomtroopers except Megane have been kidnapped. Ataru is saved from captivity by Mendou's little sister Ryoko, who gives him supplies and even a motorcycle to save Lum with.