Darix is a former boyfriend of Ali.
When Steve and Ali take a break from searching for their missing chaperone Marty on a class trip to Philadelphia in "Smooshed: A Love Story", they stop at a restaurant known for a spicy food. Steve notes at the food isn't the only thing spicy, acknowledging Darix and Royce kissing. Ali is upset by Derix' appearance, and eventually informs Steve that he was her ex-boyfriend, although she tries to deny the existence of love. When she refuses to leave and appear to be defeated, Steve eats a Carolina Reaper pepper, which gives them a handy excuse to leave so he can go to the hospital.