Masatoshi Kosaka

Masatoshi Kosaka (小坂 正利, Kosaka Masatoshi) is a student who the Sket Dan question about the "Paint-Man" incident.

Personality
Masatoshi Kosaka is known for his silver tongue and tendency to court multiple girls at once.

Plot
After the Sket Dan mention this information to his then-girlfriend Yumi, she dumps him and he appears genuinely depressed as a result. He shows up again in chapter 167 still trying unsuccessfully to convince Yumi that he is in love with her.