If i remember correctly, that is the same guy who gives the idea on assasinate Nakyum to Jihwa... jihwa clearly don't like that idea... But that guy knows to manipulate him..
I bet the reason he's doing this is killing 2 birds on one stone... getting rid Nakyum by Jihwa and getting rid Jihwa by Seungho.
Now i know why he made Seungho realize his feeling to Nakyum. Deym genius
Finally