Rito Yuuki is a hapless high school teenager who's hopelessly in love with the shy, gentle Haruna Sairenji, but just can't work up the nerve to confess his feelings. One night while taking a bath, however, a gorgeous (and naked!) alien princess named Lala Satalin Deviluke crash-lands into his bathtub, and things just spiral out of control from there... Note that "To-Love-Ru" is a multilingual Pun on the word "trouble;" in Japanese, these are pronounced identically (toraburu).