I agree with bubblegum_kiss, Du should be sure that it's worth thw possible consequences. Things happens and secrets get out. I personally would not reccomend it, but Du are old enough to make your own choices. Good luck. :)
As long as your prepared for what's going to happen with you, if one of the guys is dating somebody else then your going to really have it from one of those girls.
I wouldn't do it because it would come with a bad rep when it got out...even if Du are single honestly (I'm just stating the facts) hooking up with two guys in one night makes Du look like a HUGE slut.
Nothing is ever ok oder not ok in my eyes. It's all about what Du as an individual person thinks is best for Du and the people Du are associated with. People will always have one night stands, have group-sex with Friends oder associates and to be honest i see nothing wrong with that. It's your life, Du may do with it as Du please.
All i can say is be sure of the consequences and stay safe. Even if Du don't want people to know what you're up to, let at least one person know where Du will be in case something happens and Du go missing. Always protect yourself sexually, not only with condoms to protect Du from STD's but also with some birth-control, be it pill, injection, implant whatever. It's up to Du what Du choose to do in your life, i'm not going to judge you, but as long as Du know the risks and take precautions to minimise them, i see no problem in it.
