Nat is the friendly owner of The Peach Pit, a popular diner in Beverly Hills. In the first series, he was sometimes present to overhear what the various teenage or young adult characters were going through, offering words of support.
Nat suffered a heart attack during the fourth season, leading to the possibility of the Peach Pit's closing. Brandon sacrificed much of his time to oversee the diner's functioning while Nat recuperated. The Peach Pit was saved when Dylan McKay bought out Nat's cousin's share. Nat and Dylan's partnership was further explored in season five; particularly during Dylan's massive relapse. During this period, The Peach Pit After Dark made its debut as an after hours night club owned by Nat and Dylan and run by various members of the gang. Dylan stole money from Nat during this point. During Dylan's intervention, Nat pointed out how hurt he was that Dylan stole from him.
During the sixth season, Nat rekindled his romance with his former girlfriend, Joan Diamond, whom he hadn't seen in over two decades. Joan became pregnant, and she and Nat got engaged. She went into labor in the middle of the wedding ceremony and, at the hospital, insisted on completing the marriage vows before going into the delivery room. She gave birth to Nat's only child, a son named Frankie. Nat also escorted Donna Martin down the aisle at her wedding to David Silver in the series finale. Donna's father, Dr. John Martin, died of a stroke midway through the final season of the series.
- "Ugh! I'm never gonna learn to work this machine. Whatever happened to regular coffee? Willie!"(working an espresso machine)
- – We're Not in Kansas Anymore
- Nat inherited the Peach Pit from his father, Sal, who was well known among his clientele.
- According to Nat, his father was very strict