Hello hello!

It looks a lot like Yoneda Kou's art-style, she made some great yaoi manga's and dj's.

Yeah I thought about that too. But don't worry, at the end of the manga, someone asked for the picture in the comments as well and she had the answer ; "NightS" ! :D

It's an illustration. NightS is a different manga.

ooooh )':

Sensei drew characters of NightS
http://www.mangago.zone/read-manga/nights/