Cancer males too clingy?

Ok, so here goes. I'm a leo female and I know this male cancer. We have hung out on 2 occasions, and talked on the phone for hours. While he is attractive, I have made it clear to him that I am not attracted to him (literally saying that to his face), and also making it clear that I would just like to remain friends since thats all I see him as.
So, the day afterwards, for the next 3-4 days, I got a txt from him everyday. Communicaion has not been the same. Our phone conversations are different then in the past. BUT, its weird, am I over reacting or are cancers usually this clingy— I mean me being a leo, I like people, but I like my space as well. Do cancer's always act like this. (Keep in mind we have never kissed)...So, I can't understand.
Also, all of his friends are girls and I asked him if he was gay and he said no. So, I dunno what to do. Should I back away from this cancer. or should I confront him about being too clingy like that? What do you think cancers??

I wouldn't say clingy, but very protective over females that they have interest in. I am just SUGGESTING and giving you some of my past experience, but since you told him that you were not interested--watch out. He is going to pursue, pursue, pursue until you finally start or confess that you LIKE him, and then he will disappear on you, just to come back to you once you don't show him any interest again. Complex man indeed. Just go with the FLOW and remain just as complex and challenging as he is, or you could just be easy and make him lose interest in you very quickly or within a few months after he gets everything he wants from you.