Usagi no Tsuno

Usagi no Tsuno (兎の角) is a manga series by Nozomi Mutsuki. It was serialized in Fellows!.

Plot
Amazawa Izumi and Mashiro Aya meet at the Amazawa Girls Academy. Aya was hired by Izumi's father to get rid of the "Midnight Ghost" a mysterious apparition which appears at midnight. Any girls who meet it fall into a deep sleep and won't regain consciousness. Aya gets on Izumi's nerves with her carefree attitude, but can they overcome their differences and be successful? What other poltergeists await them? How will their relationship develop?