Rock Eater Episode 2

"One day, I'll destroy you with this spear," swore Ushio, as his odd adventures with the giant youkai which he named "Tora" began. Tora was also looking for an opportunity to eat Ushio. While this bizarre combination became a thing, an old stone armor that was in one of the old school buildings of Ushio's junior high assaulted some of the students. One by one, students were being turned to stone, and then the evil spirit was now going after Ushio's childhood friends, Asako and Mayuko...