i hate my classmates

I have the weirdest classmates of all time. One time some girl came up to me and my friend and asked if she could twerk on me and my friend?? There was also this one person who kept touching me and overall being a weirdo. She went up to me, GRABBING ME BY THE SHOULDER and saying "We have a class together lets be friends" and then went on about how she can't just go up and talk to random people. There was this time where she noticed I didn't want to be touched and a few days later she said she wouldn't touch me again, WHILE TOUCHING ME?? and somehow she thought I'd buy her some choccolate?? She stopped me while we were walking backk to class after lunch amd GRABBED me and told me to 'please buy her chocolate.' I can't stand her at all