Transferred to another world, but I'm saving the world of an Otome game!?

Chapter 16: The Seven Trials and me?!
Chapter 15: The Culprit and Me?!
Chapter 17: Riko does to me and?!
Chapter 15: The Culprit and Me?!
Chapter 17: Riko does to me and?!
A two-part one-shot about a guy accidentally transported to an Otome game by his sister. To get out, he needs to clear a love route, but he tries his best to find another way.