Hello all !
I'm searching for hours and hours a manga that I read long time ago, but I don't success to find it.

What I remember :

• at the beginning of the story, the action taked place in high school, and the high school was in japanese countryside
• there was superpowers or sci fi cause at least one of the pupils had powers, and I think it was not a good thing for the authority
• there was something with a butterfly (power, weapon, aesthetic...)
• it was very well drawn

I read the first chapters in summer 2014-2015, so it's a recent manga but not too recent.

Thanks very much to all people that will help me 🙂

Oh and sorry for the bad english, I'm French.