In the beginning, he lives alone with his sister due to their parents always away to work. Rito is quite shy when it comes to girls. He has a crush on a girl named Haruna Sairenji, whom he constantly tries to confess to but always backfires on him (a running gag in the series). One day, after another failed attempt to do so, he encounters an (naked) alien princess named Lala while in his bathtub, who is on the run from home because of her father forcing her into arranged marriage. It's stated in the anime that due to accidentally groping her breasts he is now engaged to her. At first, she only pretends to show affectionate feelings for Rito at the beginning of the story so that she can stay on Earth, but came to truly love him and desire to marry him for real and came to live at his home.