Also, I know everyone is anyone with MC answer (including me) but let's remember two things
1) There is that whole "idols can't have relationships" and he knows about it, that's why he is keeping his distance
2) She also knows this, that's why she got that absurd idea of "I will make him fall in love with me but will not follow trough it" (which honestly, was not really nice. Sure, we all know that in the end she will follow to a relationship, but we need to remember how she is acting now)
There are two ways to this stalemate ends
MC feelings get too strong, and he is not able to hold it anymore
FMC decides that she can't keep with this game and make a real move (at least, one that make it clear that she is betting her career to get together with him)
Let's also remember that, if he had confessed his feelings and with her current mindset, she would end rejecting him.