Read manga: Gakuen Heaven - Double Scramble - Kasahara Hen

manga
Summary:

Asahina Yuki, a young man with no special skills save for good luck, was invited to attend Bell Liberty, a legendary high school for elite students. Immediately after arriving, he was given an armband by a mysterious ninja who begged him to protect the school. That armband is the proof of being the Ace of the school - the student council president!