This chapter showed the mind of Mari and their personalities. I guess.
[spoilers]
.
.
.
.
Mari's mother hated Mari's father's mother. An old tradition in Japan is for the grandparents to name the child. Mari's father sided with the grandmother to name Mari as Fumiko, while Mari's mother wanted the name to be Mari.
When Mari's grandmother died, Mari's mother forced the new name on the young Fumiko. The stress of her parents fighting, her grandmother's death and her mother's instability, caused an irreconcilable division between her love for her grandmother and what her mother expected of her. This ultimately resulted in Multiple Personality Disorder. The young Fumiko "went to sleep" and the Mari her mother wanted awoke.
In High School, she falls in love with Yori, but this conflicted with what was expected of her, which was Mari's sole purpose. After diligently stalking and emulating the real Komori for months, she created a new Komori personality, a man who could love Yori.
Thank anonymous I was thinking something along those lines but culdnt quite explain it. Do you think any of the other personalities will resurface?

This story too confusing what the hell is going on.