Tawarayama is En and Atsushi's instructor who was supposedly killed after tripping over Wombat and tumbling down a flight of stairs. Wombat clarifies he's not actually dead—just severely incapacitated. The catch is that Wombat has to stick close to him constantly to prevent his body from decomposing, and he basically uses Tawarayama as cover to blend in.
In "Love, Training Camp and Toothbrushes," Tawarayama briefly comes to, but gets injured again almost immediately and slips back into a coma. Since no one actually saw him wake up, they're genuinely unsure whether he's some kind of walking corpse or if he'll just snap back to consciousness one day.
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