I got excited after watching the anime. The protagonist is Shinto Ainosuke's uncle but not the heir, and he is a classmate with Koyomi and Ranga. He is an athletic genius... But not interested in all sports. He was forced by his friend to go skateboarding together and witnessed the dark history of his "eldest" nephew. If there is any discrepancy, it is all personal information.
Intention: Don't abuse, get high