Momo is the younger sister of Lala, the alien princess who has long sincebeen engaged to the human Rito. Although Rito's heart continues to waverbetween Lala and his first crush, Haruna, Momo finds herself unable to deny thefeelings she has for the hapless human male. Instead of giving up, Momoattempts to surround Rito with a harem of beautiful women, all working towardsurging him to marry Lala, become crowned as King, and as a result, be allowed tomarry his entire harem--Momo included!