Nagai Towa

Finding a mysterious egg during the school trip, he was taken to a different world. Although he is unwilling to fight in a strange armor in that world, he can basically control it thanks to his previous fighting experience.
He is trying to find a way to return to his original world step by step with his either originally optimistic attitude or the thought that nature will take its course.
He is also concerned about his young sister Hirose, who used to live with him, but now is left alone.