Ataru's complete inability to learn from consequences becomes the engine of every joke, every romantic disaster, every escalation. The animation moves like it's having fun at the premise's expense, all fluid chaos and character acting that makes his perpetual suffering look effortless. You're watching someone repeatedly choose the worst possible option and somehow stumble into the exact outcome that makes everything worse, and the show's timing is so sharp it feels new even when the gags are older than most viewers.

When an alien race called the Oni threatens to invade Earth, they agree to leave on one condition: a randomly chosen human must beat Lum, the Oni leader's daughter, in a one-on-one game of tag. The pick falls on Ataru Moroboshi, a lecherous and chronically unlucky high schooler. With ten days to grab Lum's horns, he finds the task nearly hopeless against her alien powers, until a marriage promise from his childhood friend Shinobu Miyake spurs him on and underhanded tactics let him catch her off guard. The victory backfires. Lum mistakenly believes Ataru wants to marry her and moves in with him, and the womanizer spends his days trying to shake off his clingy new admirer while patching things up with Shinobu. Comedy, romance, science fiction and the supernatural mix as the alien princess takes over his love life.