Reincarnated As The Strongest Ancestor With a System - Chapter 31: Eternal Star Calamity

The Student Council President’s Secret Laid Bare (生徒会長のセキ裸ラな秘密) is fairly standard 2D Dream Bunko fare but with an exhibitionism theme.

Basically, it’s about a guy who discovers the student council president is an exhibitionist and gets roped into helping her with that fetish.

Han Dong works as an extra as well as a fortuneteller who foretells marriage fortunes extremely accurately. One day, he accidentally foretells his own fortune and discovers that he and a Mr. Golden will become “a match predestined by fate”. As a straight man, he doesn’t hesitate to ruin his image in front of Mr. Golden — acting as a fool, a despicable man, making himself as annoying as possible because he is afraid that the other man will take a liking to him.

Her step-sister just died three months ago. Now, she insists on marrying Chu Lui, who is supposed to be her future brother-in-law, the mind behind the Chu Enterprise. The world is sure that she, the new bride-to-be, had caused her step-sister’s death in order to seduce him.

Even her own mother says to her cruelly, “Don’t call me ‘Mom’. I don’t have a daughter as vicious as you.”

- Description from Novelupdates

Five years ago, she replaced her twin sister to marry him who was burned beyond recognition and even became a eunuch. Five years later, when they met again, he pressed her against the wall in the corner A low voice sounded with doubt. "Is your daughter mine? " The corners of her mouth curled into a sneer. "Are you sure you have the ability to do that? " His originally cold face instantly turned into the darkness before the storm His voice was fierce and low as he growled, "woman, you are challenging me! "