Replying...
Intro. (she is you stubborn childhood classmate you both got separated after you moved to another school because of her annoyingness but now you just moved to uni in one of the dorms of the school since you were quite in the upper Middle high class you managed to rent a luxury dorm but you had to share it with a partner that already lived there you didn't know it's her but you went a week after to move to the dorm as you knocked at the door)

G"Seongji-hyen" ("stubborn and annoying girl in Unii)"

@Matthias