Umm the fact that Jae likes Hyung suk is about as obvious as the author can make it already. What really bugs me though, is weather Jae is in love with Hyung suk now pretty face, or if he likes Hyung suk character, because that's the whole point of this manwha, The inside or the outside. I would totally be sad if all the love that Jae had for Hyung suk is as shallow as the that.
umm, well regular Hyung Suk has not really had any face time with Jae yeol. I'm going to be a little rude here and say,if you take a look at some of the beginning chapters something is going on with Jae yeol's family.
1. when he went on break he was speaking with his mother-I believe-and she said something about being sorry for him being alone.
2. Hyung suk-transformed-said something about not bad mouthing the mother, and that is when quote-unquote-quiet Jae yeol did something. that is protect someone as the girls surprising noted when jinsuk tried to hit Hyung suk.
3. then there is the later chapters. the eldest brother said, how dare you take the little sister with you to that shitty or cheap school...something along those lines. Jae yeol never really responded, just looked abashed. it was the sister who intervened.
looking at those three things, Jae yeol could be 1. disowned and supported by the mother (but I doubt it), 2. an illegitimate child, 3. or three someone who brought shame to the family. there could be a fourth reason that I haven't though of, but I'm not smart enough to deduce it yet.
the previous theories don't really fit, because businesses still treat him like an heir, and none of the students treat him like he did something shameful. but, the second seems to me at least more reasonable, as he reacted to Hyung Suk's mother defense. moreover, everyone stated that before he grabbed Jinsuk he was always quiet and unnoticed. he was implied to be a loner, until the incident, and I find it convenient that he interacted along with the previous incidents I noted that his mother was what triggered him.
looking at those little hints something can be guessed that Jae yeol has family issues.
Also, Jae yeol does not intervene unless it is related to Hyung Suk. when-and I will call the regular Hyung suk chibi-Chibi Hyung suk talked about how his mother was ailing and gathering cardboard for money, Jae yeol intervened and brought a mass amount for the hotel.
He could've ignored him. Also, when Hyung Suk was going home, transformed to get the money that was stolen from chibi, Jae yel intervened. in both instances the mother was mentioned.
Unfortunately, as you noted we do not know with those two instances if Jae yeol has feelings for chibi, or if he is more attracted to Hyung suk transformed. we need more proof.
But, seeing as he did not react to the transfer student for like 2 to 3 chapters, and he only reacted when he defended the mother of "another person, or rather a pig," as far as he was concerned, I think it shows that Jae Yeol could care more for a person on the inside than their appearance.
Remember Yui, Ha Neul, and even Jinsuk's gang, were never nice to chibi unless 1. someone else was there to defend him (Vasco) or 2. Beautiful Hyung suk was there or said something. The moment they were alone with Chibi, they treated him like crap.
But, Jae Yeol has been alone with Hyung suk a couple of times in his chibi form, and he like Vasco, never showed a change in demeanor.
So, I believe that we can have more hope for Jae yeol liking both. but, we have to wait.
Okay, can I just say that Jae yeol must have feelings of some kind for hyung suk? Never mind, that hyung suk does not notice or does not have feelings himself-other than friendship-for Jae yeol. But, jaeyeol does have something going on. SPOILER ALERT...
1. When girls were commenting on his clothes he bought a lot of clothes for hyung suk. Then at the end it was shown that he wrote a lot of notes wanting to be friends.
2. During the exams he literally gave hyung suk an expensive tutoring disk.
3.he went to incredible lengths to get the money, hat hyung sucks bully stole from him...And attempt to carry hyung suk when he thought his tears were of pain.
4. After hyung suk said he needs a place for the puppies and that it has to be someone good so he can let the mom visit, he took them in even though he’s scared of dogs.
5. During the the second hand ran a arc, he quick smoking conveniently after some boys told him how quitting smoking got him a lover...
6. He would let his relative cling onto hyung suk during the outing arc.
There are more but legit, he has to at least have a boy crush.