1. Brother in love with oni-chan, after seeing his face while reaching orgasm. Oni-chan in love with father, after he saved him from the facility where he was as a child. Father that doesn't know a thing about all this and is getting remarried.
2. Re-encounter of classmates from middleschool. One is a AV actor and the other a grade-student, in love with each other but keep it in secret.
Hiren