I do it because I get pleasure from it. The taboo of it is what turns me on a lot: Knowing that the world basically tells you it's wrong, that you shouldn't do this, but I still do it anyway. I like that the guy is feeling super good from my desire to suck cock, but I don't necessarily care about him personally. Sometimes in the moment, I'll stop and realize how crazy it is that here I am with a man's penis in my mouth, and it will make me excited at how perverted I am. I just feel very safe when it's sex with a man. It's like pure sex, nothing else about life is part of it. With women, I feel like there's still pressure, to be a man, to perform, there's her expectation of why she's having sex with you which usually is not just about sex only.
It's much more relaxing with a man because you're both there for the same mutual reason: cock, pleasure, cum. You can forget everything else in your life and all you have to do is focus on the hard penis in front of you. It's like a comfort zone where I feel at peace. The best part about cock is that you get so much feedback for doing a good job: he gets harder and harder, he leaks sweet precum, his moans of enjoyment, his heavy breathing until he starts twitching and losing control until...
Just the thought of what it is that I'm doing exactly really gets me off. That his penis is his most cherished and sensitive part of his body, that it is responsible for so much of his pleasure, he would protect it with his life, but he trusts me and lets me have it to kiss and lick and suck and pleasure. And the hottest part of all is, all of that pleasure, all of those good feelings he's felt the past however many minutes, it's all gathering and concentrating into a physical form, the ultimate reason that you've got a man's cock in your mouth in the first place. Unlike a girl who can lie about enjoying sex, that moment when his head is so big and swollen, his moans so loud and uncontrollable as he violently ejaculates his hot sperm in your mouth, it's the ultimate proof that YOU gave him all of this pleasure and now you're taking it all from him, his pleasure becomes your pleasure as you swallow all of his hot salty life force.