Mahoromatic

The worlds greatist android weapon has one year left to live after fending off an alien invasion. Her creators decide to let her spend the rest of her time doing whatever she wants. She chooses to become a maid and ends up working for a teenage boy who's parent have died.

This is a comedy so the premise is supposed to sound ridiculous. It's funny and it's made by the same people who made FLCL, so you know it's good.