Demetris was born in Agana, Guam and grew up in Seattle, Washington. He attended the University of Mobile and graduated in 2017 with a degree in Kinesiology with a concentration in sports administration. Demetris started swimming in Sicily, Italy at 11 and competed in London, Greece, Milan, Aviano and continued through high school. From there, he started teaching swim lessons and lifeguarding as a summer job.
While in college, Demetris helped manage several campus recreations aquatics programs including the University of South Alabama and University of Alabama-Birmingham. He is currently working on getting his MBA, and his favorite hobbies include swimming, going to the movies and hanging out with friends and family.