Mieruko-Chan Vol. 3 (manga)

To see...or not to see? Until Miko met Yuria, the pretend-not-to-see ghosts plan seemed like the best course of action. But the new substitute teacher is that creepy guy from the park--the one haunted by a bunch of ghost cats! It can't be a coincidence that Hana's life aura starts draining whenever he's in the room. Can Miko really leave her best friend to fend for herself against enemies she can't see...?