When seme (or male lead if it's shoujo/josei manga) regretting all the bad thing he has done (especially to his significant other) and trying to make amend of his wrongdoings. Some of the list has uke that is very forgiving, never forgive or died. I don't mind whichever ending, it's just the feeling of regret, from doing bad things or taking things for granted.
Most in the list are yaoi/shounen-ai genre, that's why I used term 'seme'. Feel free to add if you have anything similar in mind.
It isnt really "shonen" . But it just got "that feel" you know what i mean?? It's hard to explain. It's different than your typical yaoi. These authors have a really distinctive artstyle. If not very simplistic, its very stylized... Yknow, it's just those kind of BL where you dont mind any plot as long as the delivery, the atmosphere and the vibe is good. well, at least in my opinion.
Unique and unusual BL's
This list is in order from my most favourite to my least favourite