I read a manga some times ago, but I couldn't remember the title.
There are twin brothers,one is a delinquent and the other is nice and shy.Sometimes before school starts the shy twin got sick and had to go to the hospital.The shy twin cries because he was scared he couldn't make friends,so the delinquent twin took his stead and act as the shy twin.
I remember a scene where when the delinquent twin slipped out a punch on some guys who was bullying him or some other person.
I'm pretty sure it's a manga that a read sometimes ago but definitely not in 2017 or the last monthes of 2016 and not before 2015,because that's when I first watch anime and read manga(although this info doesn't really helped...)
Maybe its a shoujo manga ,but I'm pretty sure the story first focuses on the twins(which I don't know if shojo mangas focuses on guys.)
lWhen I read it I'm pretty sure the female characters are only sub characters(but of course not the whole manga,because I have not finished it.)
If you have any ideas about the manga,please write it in the comments.It'll really help.