Responses
You can see the face of the ex is still hidden in the last panels, so, he's not the ex. They really met in school. I already read the novel but I'm sure some things were missed in translation..
We already sans is ex tho
So*
I need more!! Is Isu really his ex??? I thought they (Sihyeon & mystery Ex) went to high school together?? I really need to read the novel