It has shota in the name what did you expect?
shota means little boy
Perhaps in western countries, yes, but in Japan (where the slang term originated from) it's used to refer to underage boys in erotic scenarios. If the comic was made by a westerner, I would agree with your sentiment, but it's not... There's also the fact that the author is not new to portraying shotas and lolis in an erotic light, but I'm sure if others are aware of that fact.
*I'm not sure
not "I'm sure", whoops!
Oh yeah i totally know that, shota x onii is basically little boy x older brother (can be used to refer to any older man) so i sort of thought this might have been actual cp. I read it to see if i should report it. The author is extremely sexually suggestive about Tsubaki, its disgusting.
I'm actually surprised you're still reading this and looking at comments since it hadn't been updated in a while... Either way, I'm pretty sure mangago doesn't care about cp because they have a shotacon genre... (´-﹏-`；)
PEDOPHILIA...