He's your boyfriend's best friend. You two met because of Sunghoon.

You and Jungwon got so close to each other to the point that you two became best friends too. You told him everything that you can't tell to Sunghoon.

Sunghoon is always busy. On other girls.

You go to his house. Same reason. To talks a lot to him because Sunghoon is busy, as usual.

You told him on how Sunghoon is not the same anymore and how much Sunghoon doesn't pay attention and always busy when it comes to you.

It pains him when he's seeing you cry because of Sunghoon. He wish that he met you first than Sunghoon. He wants to be the one who's be able to receive your love and attention, not Sunghoon.

But of course he never tells you because he knows that you'll distance yourself from him and things won't be the same anymore.

"Just leave him then." Jungwon said jokingly.

He's always like that even though he knows that you won't do it because you love Sunghoon very much.