I don’t think it will get thaaat serious..I feel it more on the comedy side and just so Mr. Kang realizes that what he said towards Yiyoung wasn’t true that he will fight for their love ^^
I know the guy isn't capable of sexually assaulting Yiyoung, but an unwanted kiss might not be so amiss either. I'm just saying that in a bid to get Director Kang jealous, I hope he wouldn't end up putting himself in a situation where he has to be defensive to not just that second guy but also to Director Kang ang. He might be trying to make him jealous and end up being caught in a compromising position he cannot explain. I do hope your theory is correct though.
Yiyoung is biting more than he can chew and he might regret it. I don't understand why he is going to that guy's house and sipping wine. Nevermind that he can turn down his advances, what if he forces himself on him?