To Love-Ru - Darkness(2012)

The story is about Yuki Rito, a high school boy who cannot confess his love for his dream girl, Haruna Sairenji. Unfortunately, one day when he returns home and goes to the bathroom, suddenly a strange girl appears out of nowhere. Her name is Lala and she comes from the planet Doiluk. Where he should sit on the throne. That's why his father wants him to marry one of the pre-selected wives, but he decides to marry Ritu to stay on earth...