Who is Gregory 'Sugar' Sweet from Four to Score and what is their importance?

Gregory 'Sugar' Stern is Sally Sweet's roommate. Sugar is a cross dresser who performs in the same band as Sally. Sugar is a domestic goddess who likes to cook and clean, making Sally's live a joy. However, when Sally becomes involved with Stephanie, Sugar becomes convinced that there is something romantic happening between them. Despite the fact that Sally is not gay, Sugar had hoped that Sally would fall in love with him if he took care of him well enough. However, this would never happened. Sugar decides that Stephanie is the reason Sally does not fall in love with him and begins a terror campaign designed to get Stephanie out of the picture. Sugar douses Stephanie's car in gasoline and firebombs her apartment. When these attempts do not work, Sugar goes after Stephanie with a gun. This attack is also futile, and Sugar goes to jail for attempted murder.