if there will be other girls there (and depending on what your bf is going to wear) i like number two the best. maybe with wedges, but flats would work as well since you are just gonna be hanging out.
if there will NOT be other girls there, then i actually like the first one the best with the black flats. it sounds like its just a hanging out with the boys night, and i think that the tshirt is perfect with hanging out with the boys.
the differing idea based on the other girls is because i think that if there are other girls there they would be slightly more dressed up, like number two with wedges, so you would feel more comfortable if someone else looked like you. but if there aren't other girls there then you might feel a little over dressed if its just a bunch of guys hanging out playing video games.
i spend a lot of time in undergrad with boys. my main circle of friends were guys (engineers no less!) and i dressed more like number one around them just hanging out than number two which would have been more of a bar look.
but its really up to you...you know the vibe of the group the best. would number two work for the group or is it just more of a tshirt kinda group?
(wow...that was a really long message about a seemingly simple question )
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"But I want you to remember, I intend this breast satirically." Susan from Coupling
I like the second outfit, but like relrel, I think if you're just hanging out with the guys, then #1 is a bit more chill. You look great in all of them, so I don't really think you can go wrong with any of them.