I'm going to let a female college friend sleep over at my place while being in a relationship because she was really drunk
Is there any special reason for her staying with you?
She is a female and I am hoping that she will be put in a compromising situation while drunk.
It is noble to protect a friend and keep them safe, but you are creating a tempting or compromising situation that will have you perceived as cheating by your girlfriend. Keep this girl out of your apartment.
It's only for a little while. What my gf doesn't know about it won't hurt her.
You are using this situation to exploit this girl for your own purposes in bringing her back to your apartment drunk. Your gf will eventually find out and leave you if you decide to go through with this.