To Love Ru follows Rito Yuuki, a high-school student who cannot confess to the girl of his dreams, Haruna Sairenji. One day when coming home and sulking in the bathtub, a mysterious, nude girl appears out of nowhere. Her name is Lala and she comes from the planet Deviluke, where she is the heir to the throne. Her father wants her to return to her home planet so she can marry one of the husband candidates, but she decides that she wants to marry Rito in order to stay on Earth.
Rito reluctantly accepts this arrangement with Lala, who quickly becomes enamored with him and tries all sorts of methods to get closer to him. But as Rito finds himself being surrounded by other girls he starts to realize that his strange harem situation might not be so bad after all…
