<human>: *cross-posting from /r/dating_advice since this also seemed like a relevant subreddit discussing guy-girl "friendships"*

I'm in a casual/undefined relationship with a guy I've been seeing for the past several months. He has a lot of female friends, some of which he is very close to. It doesn't really bother me. Guys are allowed to have female friends. 

However, long story short, I found out one of his female friends spent the night at his house. They've been hanging out since after 4pm yesterday. He lives with roommates whom he's also good friends with. I saw on his snapchat that they were all hanging out with another friend as well, so I assumed they were up drinking and that she spent the night at his place to sober up in the morning. But this was all on a work night and they have been hanging out all day prior. He works very early morning shifts, too, and she was at still at his place until very the last minute before he had to be up and at work.

He texted me good morning, and I responded, but I don't know what to say and he hasn't texted me anything back. I almost want to ask him about her/us/and if he's sleeping with anyone else (for health reasons, I prefer my partner not be sleeping with multiple women)

The whole situation got me feeling that they slept together. "Friends" can sleep together, because technically, we're "friends" as well. He's always referred to her as just a friend but now I'm realizing that his definition of friend may not be limited to platonic non-sexual relations. When we first started seeing each other he would offer for me to sleep at his place while he slept on the couch if we drank that night, so it could just be as innocent as that. But I don't know. We've already slept together a few times and still not have defined our relationship. It was fine at first but if I am one of many girls he is sleeping with and he isn't telling me...

Give me a shortened version of the text
<bot>: For guys who have a lot of female friends/are close to a lot of females, is a female friend sleeping at their place a sign something else is going on? What if alcohol was not involved and she spent the night?