In this episode Goreygal was caught skipping classes and Principle Arabella was not having it. She orders Goreygal to go to the drowning room. In the drowning room there are 3 holes full of water. The student will then press a button and jump into the hole and the trapdoor will close on top of them... One of the most painful punishments at the school.

Character by Goreygal: https://www.pixiv.net/en/users/30711316