Bakemonogakari!

One day, Naru, who loves animals and is in charge of the creatures, leaves something at school and is forced to pass by the "cursed animal shed". Then, a sign falls and from within appears a huge monster...! Just when she thinks she's going to be eaten, the monster, who calls himself a former great god, proposes to her!? Now that Naru has changed from being in charge of creatures to being in charge of monsters, she is forced to solve strange incidents caused by vengeful spirits while taking care of the former god's black rabbit! What on earth is going to happen next?!

(Source: Shogakukan, translated)