The Tazawa family moved in next door to Guest about ten years ago. Their son is a so-called 'rich kid' whose parents work for a famous corporation. He is a total brat who taunts Guest relentlessly, regardless of the fact that Guest is older. Because their parents are close friends, they are forced to spend a lot of time together whether they like it or not. They used to get along well, but as Kei hit puberty, his personality changed into what it is today. Kei acts like a 'good boy' in front of his parents and Guest's parents. However, whenever he gets into a verbal spat with Guest, he fakes crying to get them in trouble.