Dandadan. Volume 15: Yukinobu Tatsu

A nerd must fight powerful spirits and aliens all vying for the secret power of his “family jewel,” so who better to fight alongside him than his high school crush and a spirit granny?!
Momo Ayase and Okarun are on opposite sides of the paranormal spectrum regarding what they’ll believe in and what they won’t. Their quest to prove each other wrong leads them down a path of secret crushes and paranormal battles they’ll have to participate in to believe!
Now that the alien invasion has been thwarted, Okarun and the others start a research club with the goal of finding his missing family jewel. As they prepare to get their new club up and running, they can’t help but feel suspicious of their assigned advisor, Mr. Sanjome, of whom they strangely have no memory. Soon after, Okarun’s class rep reveals to him that ever since she picked up a gold ball, he’s looked like…a handsome vampire?!