As Lori discovers too late, Mark is the teacher's aide for her father at UW. He also works for Latnok.
Leaving The Rack, someone bumps into Lori and spills her drink. When she gets home, the same young man is getting out of his car and coming towards her. Thinking he is a stalker after her, she sprays him in the face, only to discover that he was coming to see Stephen, her father, as his teaching assistant at the University of Washington. They exchange witty accusations, and part expecting to see each other again.
Later, they meet and Lori discovers that he is the DJ they are looking for to dj their prom. Later, when Lori asks for Marks help with music, they become songwriting partners and Mark agrees to dj the prom.
At the beginning of Season 3, Mark is revealed to be associated with Latnok. Just when his and Lori's relationship is kicking up, Cassidy(from Latnok) warns Mark to stay away from her.