Kurosagi Hikaru is a 20-year-old college student who has never had a steady girlfriend, but he’s had a lot of one-night stands and casual sex. He’s handsome, rakish, and has no reservations about casual relationships. Then one night walking home from a party he sees a young woman playing with her dog in a park and falls instantly in love, for the first time. This girl, Yuriko, is nearly his exact opposite in experience despite her beauty and wealth. Can two people so different stand a chance at staying together, especially as Hikaru's perverted past doesn't want to leave him alone?