Caught Gf (19) being groped at party

So my gf and I met at University and have each gone home for the summer. We’re separated by a good distance.

The other night I’m looking at Insta and see her tagged in some photos from a party. I knew she had gone to it and had texted her during, she called me when she got home, all that stuff. But one of the pictures her in the background with a guy standing next to her clearly grabbing a handful of her ass.

She had never said anything about this to me during the party. Now she has a big juicy ass and all so I figured maybe just a guy got hammered and got touchy. I ask her about it and here she says it’s no big deal, that there were these four guys from high school who always used to mess with her and grab her ass a lot in school. She says they’re just friends, two have gf’s and all, and she was so used to it she didn’t even think to tell me.