Yes he is. He is just using her since he is also a vimpire who is looking to damage Yi's reputation to win over his seat on the senate.
But well his character will help our couple to realize their feelings and trust even more. Mostly her since he is already in love with her.
Why you gotta give a huge spoiler.... ┑(￣Д ￣)┍ Σ( ￣□￣||)
Why should she trust him? The only happy ending would be if he died. Ktbn.
It is not a huge spoiler. The aftermath is and I did not say anything about that. So take it as you want.
To the other reader... It is not that she should trust Yi. She cooperates with him and she kind of earn his trust.
the prez is the bad guy. I'm sure he must have set the things up