Heidayuu Sasayama

The son of a martial arts family, he's decisive, stubborn, rather mischievous and a bit cynical with the habit of being a little to frank in his speech. Heidayuu's specialty is traps, machinery and mechanics of all kinds, and his skill with them are acknowledged. The room he shares with Sanjirou is full of devices and traps they've set up. This even includes an entire extra room that the Headmaster gave him permission to build for himself in the ground under their regular room.