Heated Oven
A vaginal or anal cavity that has been slathered with a self-warming, lubricating jelly in advance of sexual play involving penetration.
After giving her undercarriage a nice warm wash in the shower, Carla made her final preparations in advance of her boyfriend's arrival home by slathering up her oring with dollop of warming gel. By the time her boyfriend got him, she had a nice heated oven ready for a good old fashioned anal plundering.
Pre-heating the Oven
For men: like sloppy seconds, except the girl you're about to bang was with another girl immediately before you. Opinion is divided about whether this improves or detracts from the quality of your subsequent experience.
Don't worry about it man! She was just in there with Crystal pre-heating the oven for you, go for it!