It is true. He basically manipulating everything and everyone around Heechan to make Heechan think that Minjae is the one for him or something like that.
Heechan was not really sure about his feeling and their relationship going forward so Minjae did "something" to lure Heechan.
The most underwhelmed & confusing end I've ever read. After that I was questioning Minjae character from the start to the very end. It will make you re-thinking Minjae true character, motives and feelings. I had to re-read everything from the very beginning.
IMO he is still a green flag. In summary, what he does is not respond to calls/texts a few times when something bad happens to him. He times coincidences in this way which makes it seem like Heechan brings him gold luck and staying apart brings bad luck. Heechan, having undergone a supernatural experience, believes it easily and agrees to move in together. BUT the fortune-teller lady does say that they weren't coincidences- their fates really are intertwined forever. So take it as you will. They're very much in love.
(=・ω・=)
It's still lying. It wouldn't be questionable if it was done just out of sillyness. But, Minjae does it out of his lack of confidence in Heechan. That, Heechan might not feel as connected in a relationship since he didn't experience love from anyone. He's scared if Heechan drifts apart.
This kind of ending where no communication happens when one of them is in doubt, raises possibility that Minjae may forever be scared of that feeling. He might repeat this kind of scenario presenting Heechan essential to his life. So if something bad happens, Heechan can feel guilty and be close to him somehow.
It's a mini tragedy that this relationship didn't reach its full potential even though both of them love each other.
I see your point! I'm probably too biased towards Minjae (and also desensitised because of yaoi toxicity ) you're absolutely right about the mini tragedy however I do think they've definitely evolved from after those incidents and onwards- also out of the story, beyond the ending- to a point Minjae feels loved and secure enough not to repeat guilt-tripping Heechan while Heechan gets a bit more expressive.
I just saw the whole thing more as an attempt of childish, harmless manipulation, because it doesn't change the fact that Heechan loves Minjae too much and would still quickly agree with him after realising it on his own. I also feel like Minjae knows love. He has been loved and left behind in the past. So my take is that his insecurity stems mainly from Heechan's nonchalance (about everything, that's just the guy he is...he's explosive but not very expressive (he doesn't deny his love for Minjae but he does get a bit shy iykwim) which makes Minjae question if he likes him back frfr (rather than the gravity of Heechan's feelings) which I feel like he sort of gets to realise and confirm slowly as Heechan is so sincere so I don't see him trying this kind of thing anymore in the future. Idk if I made sense lol kk.
I get it too. I also very much like Minjae, so it appeared more as a tragedy to me that a character like him who has someone like Heechan love him, resort to such actions.
If we think their life went on like the stories in extra (when I read the story first, it wasn't there), then it's a very happy ending of
MAJOR SPOILERS ( for other readers)
Getting accepted by Heechan's family, knowing how much sure Heechan is about him and that he actively wishes for him to be happy.
But it would a bit tragic if their life went on like how main story ended, with Minjae laughing and living with him but actually scared behind the back. It's just even if Minjae can be not destructive, the actions itself are. So it has a chance of straining the relationship despite neither of them wanting to.

Is it true that Minjae became a red flag toward the end? Σ(っ°Д °;)っ
Any Novel Reader?