It is really good game, but MC nad his mother, who he idolizes, are awful human beings.
Conclude his mother was adopted by Akemi parents, then she groomed Akemi to lesbian relationship, then dump her for father of Hikari and MC. Then he left her, probably because he realized that he married lesbian and she casually get back to Akemi to have someone to take care of her children, when she demonizes their father (headcannon, but reaction of MC when he tried to get them back, and we know that he is good husband and father to his new family hint at that).
No wonder that he is trash with relationships too: in original tomeline he cheat on Yukine (best girl btw) with Hime, then he dont pursue relationship with her, but is with Hana. Then he cheat on Hana with Hikari, then abandon Hikari for Sayumi, who he married because she is pregnant (timeline hint at that). I dont really know why anyone but his dauther and maybe his wife want to save him.