Kichi has long black hair that covers both his forehead and his eyes, similar to the hairstyles of most of the Nezu siblings. He has a round face and is identical to his twin brother, Suekichi.
Kichi is more conservative compared to his twin Suekichi, having a personality closer to Kazuma's than Suekichi. He openly enjoys playing soccer with his brother and defends both Suekichi and his sister Kyouko from Yagi.
He is shown to intrude into Ryuuichi's home once and gets stuck in the hedgerow, which is discovered by Kotarou and Ryuuichi. Ryuuichi learns the reason is due to his running away from home as he was unable to buy a game that he wanted and could not afford. He states that he loves his family a lot but could not stand "being poor", and cries in front of Ryuuichi as a result. Ryuuichi contacts Yagi, who is the best friend of Kichi's older brother, Chuukichi, for him to take his brother home. Eventually, Yagi shows up with Inomata Maria, and Chuukichi appearing soon afterwards with gifts for Ryuuichi and Inomata, as well as the game that Kichi wanted. He apologises for his brother's rash behavior and for breaking in, as he comes to understand Kichi's troubles of growing up.