It Must Be Because I'm Set Up as a Supporting Character

The only unexpected thing in this world was that after toying with the protagonist's heart and then abandoning him, the protagonist came back. In this world where the protagonist is a knight, Andrew transmigrates into it and gleefully plays every role by the protagonist's side: prince, princess, friend. Until things get out of hand: the protagonist confesses. So this is the story of a reckless uke doing everything he can to get away from the seme, only to drive the seme to become twisted.