A little sister, distraught by her big brother's suicide, is asked one question: What do you want? This story is about a girl who gets a chance to avert her brother’s fate. And that brother gets a chance to find his truth before it’s too late.

Ryouta Arata is an otaku who's just lost his job. In order to avoid becoming a NEET, he joins a PMSC, but little does he know the life of a mercenary is more grueling than he could ever imagine.