Dandadan. Volume 8: 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!
Having looked on helplessly as Momo fought the Evil , Okarun resolves to become stronger. To help with his training, Turbo Granny takes him, with Aira in tow, to the school’s music room, where they’re attacked by the portraits of composers hanging on the walls! But with some tips from Turbo Granny, Okarun is able to beat them, and he decides then and there to take on the Evil Eye!