Ochiba Jouraku

A girl that ruins Koyomi Araragi's life. She created an oddity from her past which amplified feelings of regret in others, often causing them to apologise to no end. This is likely due to her having a disease when younger, which caused her mother to "wish she never had been born," in an apologetic way and apologise to no end. Ochiba is incapable of controlling the oddity; later. Shinobu must drain her energy, thus stopping the oddity.