It's the ultimate expression of love to wear matching rings with your significant other, showing the world that you are a couple. High school student, Wataru Fujii, also wears one even though he is single. When he accidentally switches rings with a popular and handsome senior, Yuichi Kazuki, they discover that their rings pair up! Since that moment, Kazuki - who is known for being kind to all - becomes strangely harsh to Wataru. They alternate between hot and cold, as in between clashes they beg...