As he was dying, Chujin's final wish was for Ceroba to continue his research: to create a serum that would strengthen monsters to fight against humanity. To do this, she would need to obtain a Boss Monster, and a human Soul that was 'pure' - untainted by violence - and fuse them together. Chujin - a Boss Monster himself - had tested the fusion on himself several times, resulting in his terminal disease. He was very specific that Kanako be should left out of the research, even though she was also a Boss Monster. Obtaining another Boss Monster to make the serum proved extremely difficult.

Kanako eventually discovered her father's research, and insisted to her mother that she could help with the testing. In a moment of weakness born of desperation, Ceroba tested the unfinished serum on Kanako anyway, despite Chujin's fears. The test was a disaster, leaving Kanako effectively comatose, and sending Ceroba into a destructive spiral of depression.

If Clover chooses a pacifist outlook, Ceroba will see it as her last chance to fulfill Chujin's dying wish. She will do her best to befriend and manipulate Clover, with the intent of getting close enough that she can kill them, take their soul and complete the research.