Matt Dillon is Yuujirou

The author of the manga stated that he created Yuujirou inspired by Matsutarou Sakaguchi, the main character of Notari Matsutarou manga series. His appearance at debut was based on Matt Dillon. However, his appearance in later parts of the manga appears to take after Paul Stanley.

https://baki.fandom.com/wiki/Yuujirou_Hanma#Trivia