Omamori Himari

Yuuto Amakawa is a 16-year-old high school student who's never had to deal with much more than his cat allergies. However, on his birthday, an Ayakashi attacks him due to his family's historical ties to demon-slaying, and he's saved by Himari, a sword-wielding cat-woman. As the family charm that protected him from supernatural forces has worn off, Himari is tasked with keeping him safe, which puts Yuuto at the center of various supernatural conflicts and introduces him to multiple women with complicated motivations.