Jimmy Phoenix is a pre-made Sim found in the Family bin in Sim State University. He is in his freshman year of college, majoring in history. In his biography he ran off from a mysterious past, it is not explained what he did, and is trying to start a new life at Sim State.
Like Erik Swain, Jimmy has no relationships with anyone. If he is moved in with an existing household, like in other of The Sims games, he'll have acquaintance level relationships with those Sims.
Like several other Sims from Sim State University, Jimmy starts off with no gender preference. He is 72 hours away from the final exam in his first semester, when he is first moved into a household.