(v) the act of inserting the penis into a mouth in order to provide the penis with a hot tub experience, romantically. Saliva volume contained within the mouth must remain at maximum capacity to ensure optimal hot tub characteristics of the mouth. Additionally, the owner of the mouth must not consume iced beverages a minimum of thirty-two minutes prior to commencement of romantic activities. Jets optional. Tongue massage feature mandatory.
"Jenny, I'm taking my pants off cuz we're going cocktubbing..."

and

"Sally, put your iced beverage down cuz daddy wants to cocktub."

and

"Your mouth is so warm and wet, it's like a goddamn cocktub!"
by Ranch God March 22, 2014
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