Urusei Yatsura - Season 1 Episode 15
Overview: First appearance of Oyuki, Lum friend and queen of Neptune. Oyuki also has incredible ice powers. Megane and friends visit while Shinobu is nursing Ataru, who has a cold; and they discover a gate to Neptune in Ataru closet. By accident, they go through this gate and arrive on Neptune to be greeted by Lum and Oyuki.