If you're not already seeing someone and they're not already seeing someone, then there's probably no problem with it.  Just make sure to have protected sex as it would just be a slap in the face to get a disease from someone whom you'll never see again.  Some people have been in serious relationships and/or marriages that have ended in disaster, and can't bring themselves to get deeply involved with another person again.  A one-night stand or sex-buddy can often solve this problem but by doing this continually, you are denying the existance of your emotions, which may eventually cause problems.  So, I think I'd say that if you just want to have a few nights of fun before eventually settling down, then that's probably okay... just play safe and keep in touch with your feelings and listen to your gut instincts.