Seirei Tsukai no Blade Dance [Novel]

Only a pure maiden can have the privilege to contract with a spirit. At Areishia Spirit Academy, trained maidens of noble families are gathered and given an elite’s education to become elementalists. The protagonist, Kamito, accidentally peeped on a bathing girl, Claire, and ended up making a contract with the spirit she wanted. Indeed, as a male elementalist, Kamito is an irregularity whose existence was hitherto thought impossible. “You stole…my spirit…you have to take responsibility for it!” “Huh?” “You have to become my contracted spirit!” Where will Kamito’s destiny lead to?
Source: Baka-tsuki