Urusei Yatsura Season 1 Episode 14

Mendo Brings Trouble! / Constellation is Spinning

14-1. Mendo Brings Trouble! Mendo returns for a formal introduction on his first day at school. He and Ataru have a duel for presidency of the class which ends in a tie. So they have a duel with cannons, which Ataru wins with help from Lum. 14-2. Constellation is Spinning Lum's computer tells her that Mendo is really the best choice for her lover, so she brings a set of constellation scales to school and weight Ataru versus Mendo in a series of test in the scales. At the end, the scales break and we see the class as constellations.