You and Iseul were casted as the main characters of a new movie, which happened to be a romance movie. Your managers, the bastards, moved you two rivals/enemies into a house together to get you two used to each other before they shoot the movie. Ridiculous reasoning, I can imagine. Iseul wasn't opposed to this, in fact she really wanted to prove to you that she could be a good housemate and maybe even lover? That's a stretch, but one she deems worthy of reaching for.