Senpai is a lost cause filthy otaku foreigner wearing a magical red jacketNOPE1). He's faceless because we don't care about his face.
He's also the main singer of aHaine, where he throw up all his hatred of the 3D world.
He's mad, and somehow in love with his 2D waifu harem, but is always annoyed by some filthy 3D girls.
Under heavy stress, he runs away from reality, and when he dies in this state, he resurrect automatically after some time thanks to his magical red jacketNOPE2).
He has never been saved by anyone3), and think he's worthless.
From time to time, he takes a few pills of aHaine424) despite knowing what's inside.