Yuiitsu Muni no Saikyou Tamer: Koku no Subete no Guild de Monzenbaraisareta Kara, Takoku ni Itte Slow Life shimasu

Kohaku, is a tamer but doesn't have monster followers. Treated as incompetent, he was actually the only human who could tame a "phantom beast" that ordinary people could not see. A Tamer's adventure with the strongest monsters begins!