Whatever the hell you want it to mean. It's not dirty. It's just the name of famous movie actor Channing Tatum.
I'm on ubran dictionary lookin' up some slang, I come across the meaning for KD Lang, and guess what, I wanna Channing all over your Tatum
Phrased coined by Jimmy Kimmel Live! On Oscar night, Sunday February 24 2013 in reference to a spiritual phenomenon in which you commit a gracious act of pleasure upon an object.
youtube "Channing all over your Tatum"
Example 1: “I see a pretty lady all across the bar, she’s smiles at me and gets right in my car and I know I want to Channing all over her Tatum”
Example 2: “If you're pickin' up a latte at the coffee shop, and the lady puts whip cream all over top, then you know she just Channing all over your Tatum"
Example 3: It’s Oscar night and I feel blessed, I got Magic Mike and Django as my special guests, I wanna… Channing all over your Tatum"