Height: 183cm
Weight: 74kg
Birthday: September 15th
Blood Type: B
Hobbies: Reading, ink and wash paintings
Things he likes: Company, hot springs, watching baseball games
Things he dislikes: Fiendish deeds, being called Dotachin
Foods he likes: Sushi, soba with tempura, green tea
Foods he dislikes: Nothing in particular, but he's not very skilled with forks and knives.
Favorite saying: "When you are standing at the batter's box of life, don't get struck out!" - Kobayashi Shigeru (professional baseball player)

Originally part of his own gang, Kyohei is now member of the gang Dollars. He has a nickname "Dotachin" which is used by several characters in the series (mostly Izaya and Erika).

One day he got a message to join the gang Dollars. He first thought is was a joke but on the next day he saw his login name (MONTA) on the list of the members of Dollars.

Monta originated from his last name (門田), because 門 is also read as Mon and 田 (Ta) stays the same.

Him and other members never saw the leader of Dollars, but he has a suggestion who the leader is because there is only one person who could organize such a strange organization. His suspicion is on Izaya Orihara. Izaya was also the person who gave him the nickname "Dotachin".