The minor figure known as "Head Boss" represents Yotaro's criminal past. He appears upon Yotaro's prison release, pressuring him to rejoin that life shortly after Yotaro becomes Yakumo's apprentice. This creates conflict between Yotaro's old associations and his new dedication to rakugo. Yakumo intervenes by inviting the boss to witness Yotaro's debut rakugo performance. After seeing the performance, the boss acknowledges Yotaro's commitment and publicly severs ties, declaring he has no further business with him. This act signifies Yotaro's definitive break from his former life.

Later, Yotaro occasionally brings Konatsu's son, Shinnosuke, to visit the boss, sparking Yotaro's suspicion that the boss may be Shinnosuke's grandfather. Konatsu's visible discomfort during these visits suggests unresolved tension about the boss's role or their relationship. The boss's specific background or criminal operations remain undefined; his narrative function centers on embodying Yotaro's pre-rakugo existence, facilitating Yotaro's transition into the artistic world, and maintaining an ambiguous, ongoing connection to Yotaro's family through the implied link to Shinnosuke.