Seth is a very bubbly character, thanks to the likes of his "only true friend" Ryan, and is prone to not knowing when to keep his mouth shut, however this is more endearing and humorous, than irritating.
He is shown throughout the series to be self-obsessed and neurotic, with a tendency to make himself the center of attention.However, in many episodes, he proves to be a sweet and genuine guy with good intentions and a good heart, and this is often overlooked by others.They quickly strike a friendship as Ryan did not judge him like other "Newpsies" and Seth was the first to accept Ryan as a member of the household without any reservations.Soon after Ryan's arrival, Seth became friends with Marissa Cooper (Mischa Barton) and got the chance to speak to Summer Roberts (Rachel Bilson), a popular girl on whom he had a huge crush since childhood.Besides his awkwardness, his naivety in social norms and relationships contributes to his propensity to draw trouble to himself and not realizing until it's too late, a running gag in the show; for example, he has to be physically stopped by both Zach Stevens and Ryan when he tries to call his crush Alex Kelly even after she hinted for him to stay away because her ex is in town.
He quickly forms a friendship with Ryan as the latter was the first person who befriended him without any preconceived notions and without judging him.
The pair grew closer after they traveled to Tijuana together, despite Summer's denial of liking him.
She quickly turned him down for a date after seeing a few cheerleaders eyeing the pair.
Seth was further designed as an artist in the second season.
Plans of him drawing comics started at the end of the first season when executive producer Alan Heinberg impressed by Eric Wight's work asked him to be the "ghost artist".
Seth's goal was to attend Brown University, but he ends up going to Rhode Island School of Design (RISD) and continuing work on his comic book Atomic County.