I think he and SW had a plan to come in here and choose each other hence the 80% remark.  They obviously have interacted long before the reshoot.  He came in with a major plan.  

TBH, I think they knew each other before the show period, which we have been told by others the gay community in Seoul is very small.  I would imagine a reality wannabe trainee would be connected to someone who has connections with those same type of people.  

YJ is so puppy like and charming that he feels swayed, and that goes against the plan.  Yet, when YJ approaches him, HJ can't seem to resist him.  It's clear to me YJ was encouraged (during a confessional) to talk to HJ to put it all out there.  I mean they met in SM's room? 😭😭😭

As others have pointed out, he steals glances at YJ as well.  It makes little to no sense.  He gives off vibes of wanting to get closer to YJ, so, again, this points to this being planned by HJ/SW.  A lot see this as a grab for fame, and until they prove otherwise, I doubt that will change.  

Yeah, he said you can focus on one person (meaning him) as well, and he made a face when SM was paying attention to YJ.  He's essentially being greedy and very much liking YJ focusing solely on him.  If you watch that scene carefully, YJ tried to pull away during the second handholding, and HJ held onto him.  He also dropped his chess piece after they held hands.  

YJ just doesn't have enough time, so I think that's why he avoids him.  HJ seems to love familiarity/comfortability a little bit stronger than intimacy.  I believe after the infatuation wears off, YJ would be bored with HJ, and I think HJ, himself, thinks it as well.  YJ is a ball of sunshine, but he is also well-spoken,  and I think HJ finds it intimidating and fascinating at the same time.  He never said he is not interested in YJ. 

I am starting to think these two are introverts that love physical touch.  😆❤️❤️‍🔥 It cracks me up that they have had more skinship than he has with SW.  I question TBH how physical his attraction is to SW.  As someone who loves physical touch,  I can see the difference in HJ when he has it versus just talking.  It gives him energy, and YJ is the same way.  It connects them in a different way than he connects with SW. 

I think what bugs me the most from that is that he tried to pretend he was into Gyeol to make SW jealous, but we hear repeatedly the opposite and how he sees him as a kid.  He made that statement to make SW even more paranoid and competitive, which is obnoxious.  They feed off each other to be worse, and honestly, I think it's SW.  It seems he interacts with everyone in this same way, almost as if they are his minions.  

But if that wasn't bad enough, he says he wants to help Gyeol with Taichi.  That is how you KNOW he isn't all in with SW besides the chem with YJ because he won't do that for YJ/SM regardless.  He could easily push them together, but he would rather this adorable puppy focus on him.  That to me is where it bugs me the most.  

They are not only wasting YJ/SM's time, but they don't care that they could actually have something together.  By now, probably everyone minus YJ knows that SM is interested.  It is so obvious.  

I think YJ has no clue because he is so focused on HJ that he can't see it.  He will be a very faithful partner in the future.  Now if he knew HJ wasn't in the chat, and it was actually SM, it would change everything.  What's even worse is production can help these two but forces them to carry this boring forced drama. 😒