Trapped with My Rival Season 1

On the day of the College Entrance Exam, childhood rivals Sean and Drew Morgan are trapped in a flood. They take shelter in an abandoned bomb shelter and get bound by a BL dating system. To survive, the two straight boys have to finish intimate tasks, growing secret affection amid constant bickering. The System rebuilds the shelter and grants them a son and daughter, forming their noisy yet warm family at the end of the world.