I'm not sure if this is considered a spoiler so read my comment at your own risk!!!!
In the novel he blushes out of embarrassment not out of romantic interest. Because he knows his place, so to speak, and given what happened when he first confessed he knows he and the ML are in different worlds. He's uncomfortable and feels out of place. And while the ML is being a douche the MC understands his character as being someone who is more than the sum of his flaws. (^__^) Sorry, I fell in love with the novel and can't stop talking about it. Hope you stay with this!
Ohhww thanks for clarifying!
Please spoil what happened after they went into a highly secretive bar for chaebols??
Jesus christ ml is just being the biggest dick ever and mc just stupidly blushes everytime