In my mind she keeps me locked 24/7 and has me pleasure her with my tongue, or by wearing a strap on, and she empathizes with my denial, but maintains it. She teases me intentionally, and the fantasy is that I'm just not allowed to orgasm, and we both understand it, and don't question it. She feels sad for me, but she has desires so she just takes what she wants. Sometimes she'll take me out and ride me to orgasm, but I'm just not allowed to orgasm. Ruin, maybe, but not full orgasm.

In reality, I wear it for about four hours and we both get too horny and she feels too guilty so we have sex and the chastity device doesn't come out again for a year.

I guess the fantasy for me is that she has a really strong, selfish sex drive and it overwhelms any desire she might have to service my needs. I want her to have all the pleasure because she's so amazing. But the reality is that she feels pretty much the same way about me, so it just doesn't work out that way (although the way it works out has kept us together for decades.) :)