Now before y'all come after me, Yes, Song is such a sweetheart now and has the right intentions, but imagine being in Mu's shoes for a sec. He's basically always on his own, away from all his family and friends, and really has no other life other then in the laboratory. And when he finally meets this wonderful guy Andrew who made him feel like someone who he could start to rely on for comfort and start to love, it turns out to be Song, the same guy who is the reason he used to get treated like absolute shit and now has been lying to him this entire time. Song should've tried to tell Mu who he really was before meeting up and doing intimate stuff together
still doesnt give you an excuse to rape someone