This is the term used to describe dried-up, crusty, and usually week-old semen that has been resting on a man's penis or scrotum for an extended period of time. From-Under Cheese comes from sloppy masturbation most of the time, but can also be a result of complete uncleanliness.
Bitch: OMG I'm soooo fuckkkin drunk...I wanna suck your fuckkkin dick...haha
Me: Ight bitch. Lick the From-Under Cheese off while you're at it.
Joe was beating off for 2 straight hours and had a load of From-Under Cheese under there.
Eminem (Crack a Bottle): Kiss my butt, lick From-Under Cheese from under my nuts.
Although 'wank' usually refers to masturbation, in Philadelphia, it is used for absolutely anything. Similar in meaning to 'jawn,' 'wank' bascially takes on the verb form. 'Wank' is predominantly used when something small is done or accomplished.
Me: Look at muh beautiful half-court J nigga!
Niggaz: Shyt you aint makin this jawn nigga! Who you tryna play?
Me: (Makes Shot) Wank.