I feel like a lot of you are also overcomplicating the experience of reading this. Remember how the friend said that the ML loved before but was hurt quite a lot? And it happened a lot of times? I honestly just see him as some guy who's been hurt a lot so he chose to be like that now. An easygoing person not going overboard with his emotions. It's like there's a wall around him. He likes having company thus dating the MC but he doesn't go too deep. He's that person who functions when needed. He's not "manipulative" or evil. He just isn't open enough yet for us to see what's in his mind. He's not too emotionally invested in the relationship yet as well.
So I had this older guy I've been calling master in private and online because he taught me stuff in calligraphy arts. I got too comfy with that and one day we were conversing online and addressed him as "master". I didn't know how weird it was for other people until someone commented on our conversation with "what is this between you two is this a bdsm thing-" and oh boy was I so embarrassed to the core.
I guess here people didn't mind our little mc calling the ml "master" because it's quite common in asia to address someone like that if they're knowledgeable in certain fields. It's like "Shi Fu" or in japanese sense, "sensei".
I can't help but laugh at the thought that had this been a different BL that argument would have lasted for 25 more chapters.
I was thinking that right now.