Huh??? What abuse? What trauma??? Wtf these tags. The MC was just determined to repress his sexuality to follow the orders of his religious mother/parents.
Both stories have a main character (well, secondary) who are strict in following the rules - for different reasons.
Ch 1-2 is about someone who's raised up in a religious environment - anything related to sex is forbidden. However, he gets set-up by his mother with someone in the church, so he has to learn about sex and get over his aversion towards sex - he does this by hiring a prostitute who happens to be an intern in his office.
9/10
Ch 3-4 is about someone who is simply strict in following the rules of society, for no reason aside from wanting to conform to society. He is in love with his brother-in-law. His student learns about this and tries to seduce him/help him move on. 6/10
Also, there's no s&m here. Just a bit of domination, and a blindfold.
Yoru no Rakka