I was still half hard, so there was a sense in which my cock felt weightier, more substantial, than if i’d been fully erect. An erect cock has no weight; it’s self-supporting, and although it has mass it bobs about like a balloon. I felt good, and comfortable, sliding down her throat, knowing that she’d feel me growing fully hard in her mouth, and that this would turn her on.

But after perhaps a minute she made to pull back. She’d done that the previous time she’d sucked my cock. Her jaw got tired, and she sometimes tried to rest and take a little less of me . But I wasn’t in the mood to allow her to be half-hearted, so I tightened my grip on her hair, pulled her mouth forward, and thrust deeper. Then, sighing happily, I started to move gently, fucking her mouth.

This happened twice more over the next couple of minutes, and the second time I took my belt off, enjoying the recognition in her eyes at that gesture, and gave her bottom six smart whacks. Then I put the belt round the back of her neck, and used it to keep her serving, unable to back away. 

I was sure that she was feeling properly controlled. But then she made a gesture I hadn’t seen before. She held her hands up in the air, half-closed, her wrists flapping. I watched. It seemed very feminine, and very helpless. 

Only then, at last, the light went on in my brain, and I pulled out of her mouth quickly. She sucked in air. Oh, I realised, far too late; she couldn’t breath.  

I’d never choked a woman before, in fellatio or in any other way. I don’t like breath play. I don’t like the risk, and I don’t like the symbolism of it.

So I helped her up. I kissed her. I apologised. I told her how I’d misread the way she’d tried to pull back. She said she’d known why I’d done that. In our previous session, I’d let her rest her jaw when she sucked my cock, but I’d told her that next time I wouldn’t be so lenient. I’d said that she had to focus on my pleasure and not her comfort. So she knew what I thought was happening. 

I said if anything like that happened again, where she couldn’t speak, then she should just hit the side of my knee. That’d count as a safe word. I apologised for not having thought of that before. 

So she was in my arms, and holding me back while I held her. I was forgiven, more or less. But I’d frightened her, and there were tears in her eyes.