Gouya Daisuke

Onodera Goushi is an highschooler who isn't much noticed in other people's daily life, in a sense, his life feels like it would be the same if he wasn't around, then one day while returning from school he finds himself in a life-death situation and a strange girl named Honoka saves him by sending him in another world, he then gets sent to the "Demon Nation" where many non humans live and where he is able to meet the Mahou who is... an anime otaku!?!?

In the midst of a terrorist attack that kills all his classmates, Tohru Kuroe knows the chances of seeing yet another woman die makes Tohru pick up an abandoned gun - The beast awakens; taking over. When Tohru comes to his senses, he finds he is now a killer. Finding out he was genetically engineered to be a killer, his codename is D-17, Tohru continues his 'normal' life amidst challengers threatening his life and those around him.