fabwank
You get a boner from looking at Facebook pictures of people you know. It usually happens when your hot friend shows off their nudist camp pics and you can't control your wanking.
My friend posted a nudist camp photo and I had to leave the room to finish my wanking.
I saw my crush at the nudist camp and I got a boner during history class.
He posted a group photo and I had to hide my phone under my shirt.