Gabriel was enrolled at Valemont University at one point. He's the person to contact to get pre-written papers and answers for tests at the university, helping others cheat in exchange for information on the university. He's originally cloaked in mystery, but Sophie Fields a.k.a. Maggie Gracen kept digging for answers.
-Spoilers Alert- Edit
Gabriel was Eric Gracen's best friend at Valemont University. Together they were gathering evidence of vampires being real and running the university. He became interested in Sophie/Maggie and worked with her to help uncover the mystery surrounding Eric's disappearance.