It means your thinking about him. biologically, we aren't meant to be in relationships the way they are designed. we are competitive, greedy, and most importantly, curious creatures. the reason you think about this other guy is because your interested, no matter how you slice it. that's totally alright. he won't respect you if he knows your flirting in your relationship, but by all means, give him your friendship, and let your emotions guild you from their. in the mean time, see what he has that your currently boyfriend is missing, and apply the same analysis towards your own needs and both parties. marriage should be forever, but it isn't. children are permanent. relationships are fun, but childish. but don't screw people around.