Never even occurred to me.
I mean, I had a dream last night about being chased by a genetically engineered-intelligence enhanced giant Mastadon with enormous tusks that intended to make a grease spot of me and a woman running from it, but never...never thought about Tyrannosaur Sex.
Never.

They say many of the objects in our dreams are merely symbolic for other objects, often sexual, at least according to S. Freud.