Who is Lula from Visions of Sugar Plums and what is their importance?

Lula is a file clerk at Vincent Plum's Bail Bonding Company. That is, when she's not riding shotgun with Stephanie, shopping, doing her nails, or checking out the newest bakery. She's a twenty-something black woman with a voluptuous size 12 body stuffed into a size 6 spandex