Feeling Disgusted After Unwanted Touching in Class

TW for possible SA/Sexual harassment? (please let me know if this is oversharing or against the posting guidelines) Today I was in class with a few of my (not friends, more like acquaintances. we don't talk at all outside of the few classes we have.) and the girl I sit next to usually is very touchy with me, which I'm fine with, I don't want to sound sensitive by asking her to stop touching me, because I know she does it in a joking and non-sexual way. But today she kept making sexual jokes and suggesting that I should be in a relationship with her, even though I knew it was a joke because she's pointed out that she was straight and wouldn't consider dating a trans guy, I made it clear to her that I had a girlfriend and to maybe tone it down on the jokes she was making about me. It didn't stop, and only a few minutes after that, she began to touch me much more intimately. She grabbed me by my chest and inner thighs and did this continuously from under the table and whenever the other two girls I was sitting by weren't paying attention or were away. I just sat there, letting it happen. Although I wish I didn't, I knew there would have been no way for me to speak up about it anyway. She made a joke about it to one of the girls and got caught eventually, and they both began scolding her for it. I just wish there could have been something I could do about it. I don't even know if it counts as SA. I have no idea what to do, and I feel digusted with myself for letting it happen.