77 (Sevens) ~And, two stars meet again~

There is a world where magic is widely spread. The story takes place at Tenryou International School, which is famous for an elite training school. The students are divided into three groups: Intelligence, Power and Fate. A school festival is held once a year. The main event is a battle in which a girl and two supporters are chosen from each group and they fight for a selected man, who has a special ring. Yes, the main character is the one who accidentally gets the ring.... While he is persistently chased by heroines, a mystery of their school gradually comes out...