As usual with these sorts of things I'm going to first idly speculate about this character before officially introducing her.

(Forgive me for failing the Bechdel test here. It's easier to figure out who a character is by first identifying where in the social graph they fit, and my cast is mostly male.)

One idea is that she's connected to Riley—but she doesn't "run in the same crowd" as him, she doesn't live at the dump, etc. Maybe they used to date at some point before Riley... went to live at the dump. They're still friends, they get boba together now and then, but it would take an outside force to get them to do more than occasionally cross paths. Despite being a free spirit herself she much prefers living on the grid.

She could also be connected to Jeremy since she seems not far from him in age. She seems to have a rather laid back attitude, so perhaps she played some role in convincing him not to listen to every one of his domineering mother's demands. (She could even bump into Jeremy's dad, assuming she's actually more motivated than she appears and has been taking classes at the local university.)

If she has a motorcycle (it's more convenient than a car for people with long necks), she may also be seen in Michal's shop. He does more than just repairs, you know. Maybe an opportunity for a mixup where it somehow winds up at Emmet's shop to get its enhancements.

Her name does not begin with a G (or a J). I'm thinking something like "Clarice" but that will probably change.

Adopt from  chickensnpies