Both flawed characters!
The age gap was the whole point tbh! If it were to happen when theyre a bit older it will defeat the purpose of the “he only loves me because he only knows me” problem. If Hibari was older, he would have met other people already at that point. Sumi’s guilt was based on the fact that he was the only person Hibari relies on. He didn’t want to return back the feelings because he thinks that Hibari only knows Sumi. (i hope u get it cause i dont think i explained it well)
On the other hand, Hibari’s flaws was that he’s inexperienced! That’s why he kissed Sumi without permission. And he only knows two people in his whole life (His older brother and Sumi). All his childhood he only knows to love those two people. That’s why he acted so carelessly.
Also, Sumi didn’t stop Hibari cause he thought that when Hibari turns 18, he would be independent and meet other people. Thus, abolishing the feelings Hibari had for Sumi. Sumi just didn’t expect that Hibari relies on him that much and at that point he already fell inlove with him deeply.
I think it was good cause for me its realistic! My only problem was that they had sex when Hibari was only like 18-19, it could’ve been done in a time skip lol

Smoky Nectar was so good so i really wanted to get into this- but seriously the age gap jst is weirding me tf out, like i dont like that some of the comments r like "atleast he waited for him to be legal" first of all its not even legal in japan second of all thats what pedophiles say. Like, even if this isnt textbook grooming its still.. like a bit weird aint it? i mean the older dude jst let himself get kissed by the younger one bc he had feelings for him aswell, like its his responsibility to not allow that shit to happen, i feel like this wouldve been miles better if they were both adults and it was far out in the future. These are my personal feelings tho, i stopped at chap 3 so maybe it gets better?