<human>: Throw away account...

My SO and I have a good relationship. Never had any complaints and such with how things are going. We rarely fight but once in a while we get into an argument of some sorts. 

Recently she has been looking for a new place to stay for school and is gathering people to split the cost of living in a home. Cool I am all for it and I trust her completely to make the right decisions, but one thing that makes me uncomfortable recently is that she tends to wear the lack of pants at home. 

It is totally fine for her to not wear pants at home, it is not me to judge what you do. She does this all the time since her current roommates are cool with it and they are all girls. The thing that is bothering me now currently is the fact that she will potentially be having guy roommates soon and she has some guy friends that she is close with.

We were joking around one day about her dislike of wearing pants and I mentioned its cool other than if guys were over. She laughed and said that "yeah unless it depends who, like guys I know and what not and then I don't wear them because I don't care." 
I found this a bit odd. A lot of guys like her and she is a great girl to be around, she is currently hanging and talking a lot to this guy younger than us and it makes me uncomfortable thinking about her walking around in her underwear/thong with guys around. Not that its wrong but it makes me uncomfortable because why would I want other guys to see that part of my girlfriend?

My question to you guys is if its okay that I am uncomfortable with this? I havnt brought it up with her but it is bugging me and I have been thinking about it for the rest of the day. Am I the one that is over reacting or should I mention something?

Just needed some clarification, thanks.

Give me the gist of the text in a nutshell
<bot>: Uncomfortable about my SO wearing no pants around guys and her future roommates. Is it okay for me to be uncomfortable and uneasy of the situation?