Delmar ran and operated a deli in Queens, with his sandwiches being touted as the best the borough had to offer. Peter Parker was one of his regular customers, who visited after school to buy food. Parker's frequent visits caused him and Delmar to form a friendship, as well as familiarize Delmar with Parker's aunt May, whom Delmar held an interest in. Delmar also came to know Aaron Davis as well due to his frequent visits to his Deli.
Delmar witnessed Spider-Man fighting a group of criminals wearing cardboard masks of the Avengers' faces , which he mistook as Spider-Man fighting the actual team. During the fight his shop was destroyed only for Spider-Man to come save him and his cat, Murph.
"How's your aunt?" "...She's alright." "La tía de él es una italiana bellissima." "Cómo está tu hija?" "Ten dollars." "It's five dollars!" "For that comment, it's ten dollars."
Delmar is shown to have a quite friendly and humorous attitude as seen in his interactions with Parker, and he and Parker are also good friends to the point that they know of each other's families, with Delmar knowing of Parkers aunt May and Parker knowing of Delmar's daughter.
Delmar is also quite respectful towards Parker's alter-ego Spider-Man as he was grateful to the hero for saving his life.