I went digging on the web and found out thru the novel readers who Hazel is. It’s a little spoiler-y? But I can tell you if you want.
Tell me everything
Lmfao so from what I gathered Hazel is Ash’s senior/sweetheart in highschool who everyone thought he would marry. But Hazel cheated on him and left him for someone else after they graduated. There’s apparently more back story in the novels but I’m not sure how much if it will make it in the manhwa. So I don’t wana go much deeper than that. This is the novel readers forum I was reading on tho:
https://www.novelupdatesforum.com/threads/define-the-relationship-bl.100890/page-5
who the hell is hazel