My friend gave me ass treatment

We've been friends "24m" and him "35m" for years, and one day, I decided to tell him about my secret of being obsessed with the idea of seeing my ass used by rough hands. I told him everything in the hope of letting it out of my chest but instead he took advantage of it and threatened me to reveal in case not letting him check my ass. After lots of hesitation, I got myself ready by shaving and smoothing my cutie ass. In other words, I was convinced to let us have a bit a fun. As I expected, after seeing it he wanted not only that, but also to eat, and finger my hole like a teenage girl. We also ended up with me being spanked which made me feel like a slut in a man's hands. Even though I decided to stay away from him, we went back doing it over and over, until now I can feel that my ass has got pumped up like a woman's ass in her 40s and my waist took the curvy shape, last but not least my hole is now farting all day long since he made it like an air leak. Basically, everything was unforgettable. I wonder if it's a normal thing for a man to feel that way