Shohei Harada, a Meisei High School alumnus, possesses an imposing physical presence shaped by his boxing background. His formidable reputation deters potential delinquents, yet beneath this gruff exterior lies genuine concern for others, particularly Tatsuya Uesugi, whom he frequently advises.

After graduation, Harada reappears bearing visible scars but otherwise unchanged. He develops unexplained amnesia following a traffic accident where he saves Otomi from harm, leading him to reside with the Tachibana family during recovery. He prefers sleeping in a tent in their yard while struggling to regain his memory.

His history includes persuading Tatsuya to join Meisei's boxing club over the baseball team during their high school years. Harada consistently extends guidance to Tatsuya, revealing a protective and supportive nature that transcends his intimidating demeanor.