In terms of gender, Ikuko Shimizu and Belphegor are of the opposite sex.
In some ways, Ikuko Shimizu and Belphegor are also of the same sex. …Well, I mean character.
Same sex repels, opposite sex attracts.
Putting aside the mutual attraction, these two people do repel each other.
It's a pity that no matter how different we are, no matter how much we reject each other, they will still come together.
... Because the earth is round.
Conception: