
1) Jaehyun approached Junseok because of his voice.
2) He liked their time that night, especially the cuddling in the end.
3) He was kind of sad when Junseok left the morning after they did the deed.
4) He wants to get close to him. (Hence the 'help me move my stuff' scene)
5) He wants him to text him. (He even got angry when he didn't then smiled when Junseok finally did and/or was it when he saw how cute Junseok was when he was sending him a text?)
6) He kissed him in the latest chapter.
If you think about it, he's pretty interested, isn't he? (I'm not really sure as well. XD) You're probably getting that feeling because of the way the dialogues are carried out, or maybe it's the expressions? (It feels a little off to me too. XD)
Or maybe I'm just really misreading all of the above and this is just all planned by Jaehyun to use Junseok...omg, I think Makio (from another manga) is clouding my judgement right now. XD

I'M SORRY FOR THE SPOILERS OMG I FORGOT TO PUT A WARNING ON TOP. XD

I think the uke does care for him but I can also see how you might think the way you do. :) That's unusual for me. I'm usually pretty opinionated. Lol.
And I agree with the other poster. The seme is pretty freaking adorable.
I'm kinda iffy about this couple
I just feel like uke is taking advantage of seme and not really caring for him??? Is that just me?? I mean it's been 11 chapters with almost no character development, basically uke leading seme on the entire time.