Like most of the children on Tatsumiya Island, Kazuki had no idea the earth was under invasion and strives throughout the series to understand why the adults hid this from him, and especially, why his estranged childhood friend Soushi is so willing to do whatever it takes to defend their humble island. He turns out to be an amazing fighter when he's unceremoniously tossed into the middle of a war he didn't know was raging, but fighting is never a thing of central importance to him. He turns out to be surprisingly kind and sincere, even if he rarely lets other people inside the walls he built around himself. Naturally, to someone with such a gentle nature, having to fight for his life constantly is a bewildering experience that causes him to question who he is and what he believes in. Living with only his father, Fumihiko, he does all the cooking and shopping and thus is an excellent chef. His mother, [Akane](https://anilist.co/character/191398), was assimilated by Festum long ago. He also seems to be very bad at card games as he's too honest to be good at bluffing. (Source: AnimeNfo, edited)
