My guy asks me the same question, and I never tell him because they are my fantasies. I enjoy playing them out in my mind and not having to explain why cartoons or cheese is involved. I also don't want him to try to make one come true because that puts the burden of the real world on something that is supposed to be mine. I agree with the advice here, just imagine that you're the one in my fantasies (replacing the animated cheese) and move on.
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Symian, I am not going to judge you for your animated cheese fantasies. But I will say, the impulse not to tell your guy is the smartest thing I've heard EVER. :) Also, who doesn't love cheese?