Responses
I didn't get that impression, maybe though. It's like, i could and couldn't see it because you'd have to be reading into his negativity to come to that conclusion since there isn't really anything implying that. He seems happy with the seme and his negativity can easily be chalked down to the art teacher. If it happens, this story had more depth than i was expecting and that'd be cool.

So, it looks as though the uke used to be in a relationship with his art teacher, as they "got closer" the other kids (i think they were high schoolers? The man died while they were in highschool) in class got weirded out, quit the class and told their parents about what they saw. The parents reported the teacher about him being a pedophile so the art school was closed down, the teacher disappears and ends up dead. Could've been suicide, could've been murder, who knows? He was outed as a pedophile so it's possible one of the angry parents killed him? Flash forward to the flashback where the two MC's are still in highschool and see each other at the bus stop, -news about someone dead- the seme is recommended by his brother to go visit an art museum where he meets the uke again, the uke tells the seme about his relationship with the teacher and that the teacher was the one on the news from the beginning of ch 1 that died. Flash forward to present time where the seme gets his brother to give him a ride to the uke's house, it is revealed that the two have kept a sexual relationship since back when they 1st had sex, you can see that they're both in love, but the uke is insecure and thinks the seme will leave at some point. Presumably, he thinks the seme will die as that was his trauma with his art teacher.