The Sliver Shell is a creation of Sheldons to show Jenny how big of a jerk male robots can be. in the Shells first appearence Sheldonis dismayed to find that Jenny falls for the Shell instead of realizing what a jerk he is.
The Silver Shell often shows up halfway through a battle and then takes charge, thus taking all the credit. Eventually Jenny gains a hate for him after he lied about bieng a friend of Don Prima's. Although she did ask him to a dance later on.