A fond name for, a personification of, or a euphemism alluding to an individual's real or artificial pecker. The King (Elvis) is reputed to have used the term to refer to his own dick.
Hey there, sugar-britches. Won'tcha come over here lay some lovin on Little Elvis?
In gangsta circles, a Little Elvis is a gun, a gat, a piece.
Homey started talkin' way too much smack so I pulled out my Little Elvis and ended the argument