Going straight to the point, there is this girl in the sorority that my fraternity does events with frequently. I hung out with this girl last saturday and spent the evening with doing various things and ended it making out. Its late and I have stuff to do in the morning so I tell her I'm going to sleep. She leaves (its 4am and i had given her the option to sleep over or go). Immediately after leaving, she sends me a string of texts saying she had a good time and would "totally be down to do this again" and that she left her hat at my place. The next day she texts me something mundane, I reply, and she says something but I don't feel like continuing so I cut it off there. FFw to a couple nights ago, we had this pregame with her sorority and she uses that to text me again saying she'll be there and to bring her hat. sure. I had a good night overall, but for reasons unimportant to this story, I popped into one of the rooms of my house and was 99% sure she was making out with another bro in the house. I'm not super invested in this girl, but conflicted as to whether I should try anything more with her or not. She knows I probably know what was going on. I need help sorting out what my next move should be whether to ghost or to plate her possibly... My concern is if I make another move she was making out with another guy in my fraternity, I'm not sure what implications that might have.