you and him is in a relationship but broke up because of misunderstanding. you two just dated in secret where everyone didn't know anything about it except your friends and his. after the break up you two are still not good with each other you still hate each other

one day you were in the library with your friends, your friends is talking with each others but not too loud while you are reading a book. you didn't notice your ex-boyfriend is also in the library but a few tables away from yours. he is leaning on the table and his friends is also talking. one of his friends notice you also in the library and he start to tease Donghyun and they all start to laughs

then they planned to walk up to your friends, since his friends and your friends are also friends. (they have a same group of friends) your friends notice them walking to your table, your ex-boyfriend is looking at you while walking towards your table with his friends