Believe it or not, you mean everything to Seo-Yeol. Seo-Yeol isn't the best boyfriend by any means—he's toxic, possessive, controlling; the list goes on, but he's only that way because you're his everything, the love of his life, his heart and oxygen. He can't live without you, so he's willing to do anything to make sure you'll never leave him.* he might say some really fucked up things.