I've been talking to this guy. He used to call me and we talk a lot and stuff but recently he hasn't been calling me. However, if I call him first, that's the time when he'll call me back.
One day I asked him why he hasn't called me since and he said that's the way he is. I want to know if this guy is truly interested in me or if he's just messing with me.

Maybe you should ask him if he's interested. It is odd that he had one behavior before and now it's changed.. maybe he's not sure how you feel about him so that's why he's letting you call him.. best bet, just be straight forward (don't sound crazy though) and casually ask if he's interested or whatever.. but only do that if you're comfortable doing it..

I agree with what plonak said and make sure you to are not within hearing range of others...

I am confused by your question because you posted 4 questions minutes apart from one another. Is this the same guy you kissed after meeting him at a party or your went to a party on your first date and you wanted to know if it was okay? And then he told you he has a girlfriend but his friend told you he don't. Also what are your ages can you please clarify because it hard to keep it with all your questions spread apart.

He probably still likes you. Talk to him and let him know what you feel about him not calling. I'm having the same problem with my "friend". I didn't callas much as she may have wanted. But love her more than I even did before.

I recently asked one of my guy friends why don't guys call girls back??

He said that's what guys do to see if the girl is interested in them. Others do it because they like for girls to chase them around, and some aren't interest but don't know how to tell the girl (I found that out the hard way... LOL). Be honest with him, and ask him is he interested before your feeling for him become too strong. Just ask him straight out... no hesitations.

GOOD LUCK!!

I've been talking to this guy. He used to call me and we talk a lot and stuff but recently he hasn't been calling me. However, if I call him first, that's the time when he'll call me back.
One day I asked him why he hasn't called me since and he said that's the way he is. I want to know if this guy is truly interested in me or if he's just messing with me.
Well what I think is that he was in to you but but he just slowly lost it that's probably why he stopped calling you but I could be wrong not all guys are the same maybe you should going to a party with him or hang out with and show him that you do really like or not and that's when you might the real feelings out of him. But I don't think he is trying to pplay you really you he is slowly losing interest in you so give him a reason to gain interest back in you. I'm not saying go out and have sex with but show him YOU and how YOU are and then you will have your answer