See, Greg, this is your problem. You want one huge woman when you could have multiple, smaller ones.
|—"Story for Steven"|
Marty is Greg's ex-manager, before Greg left him and his tour for Rose Quartz. He made his debut in "Story for Steven". Marty also had a brief relationship with Vidalia, during which he fathered Sour Cream before subsequently leaving them both behind in Beach City.
Before the start of the series, Marty supposedly had a successful career in the music industry. However, sometime before his return to Beach City, it's implied he fell on hard times and now has to rely on a Guacola sponsorship to stay afloat.
Marty appears as a middle-aged man (likely in his 40s), with short, platinum/gray/silver hair styled with spikes. He also has slate gray eyes and spiked teeth and wears a dark purple jacket over a navy blue hoodie over an indigo shirt. He also wears greenish-gray pants, black socks, and light brown leather shoes.
Marty appears to have aged significantly, having plenty of wrinkles, and balding platinum/gray/silver hair styled similar to his first appearance, with a tuft of hair that slightly resembles Onion's hair. He wears a dark brown jacket over a green shirt with a capital "G" on the center, and a gold chain necklace. He also wears gray pants, also with another gold chain, and golden shoes with wing-like designs on the sides. He has a pair of sunglasses similar to the ones worn by Buck Dewey, and has pierced ears with gold studs.
Marty was shown to be insensitive, uncaring, and selfish, as seen in "Story for Steven", during Greg's concert at Beach City. Rather than managing Greg's merchandise booth like he was supposed to, he was shown hanging out with Vidalia at the back of the van. He was shown to be concerned only about himself and getting what he wants. He made no excuses and didn't try to hide the fact that he is only using Greg to get what he wants; mainly money, women, and fame. This is reflected in the fact that he spent most, if not all, of his time in Beach City with Vidalia and her friends yet he has no qualms about dumping and leaving her behind once the two had to move on with the Mr. Universe tour. This behavior extends even to his son, Sour Cream, who he uses to advertise his soda.
His attitude about using people for his own gain and pleasure was summed up in his reply to Greg when he tells him he wants to stay in Beach City with Rose: "See, Greg, this is your problem: You want one huge woman when you could have multiple smaller ones.".
Whilst Marty was shown to be an extremely sly person, he wasn't completely irredeemable. Marty still made the effort to deliver Greg's royalty cheque in person and was warm to Steven upon meeting him, even allowing him to work as a roadie.
"Story for Steven"
Marty is introduced as Greg's manager and is left on the side of the road near the end of the episode.
Marty is mentioned by Vidalia and Amethyst when they talk about their past.
"Drop Beat Dad"
Marty revisits Beach City to advertise Guacola, and is still as manipulative as ever; he tells Sour Cream that he was "making up for lost time" when he "helped" him with his DJ gig. Marty reveals that the whole point of him coming to Beach City was to give Greg an envelope labeled "Star Child" that contained a check for ten million dollars.
A younger Marty makes a small cameo in the Pepe's Burgers commercial in which he sings. Greg comes up with how he could sing it with the ten million dollar check that Marty previously gave him in "Drop Beat Dad".
|1. "Gem Glow":||Absent||14. "Lars and the Cool Kids":||Absent|
|2. "Laser Light Cannon":||Absent||15. "Onion Trade":||Absent|
|3. "Cheeseburger Backpack":||Absent||16. "Steven the Sword Fighter":||Absent|
|4. "Together Breakfast":||Absent||17. "Lion 2: The Movie":||Absent|
|5. "Frybo":||Absent||18. "Beach Party":||Absent|
|6. "Cat Fingers":||Absent||19. "Rose's Room":||Absent|
|7. "Bubble Buddies":||Absent||20. "Coach Steven":||Absent|
|8. "Serious Steven":||Absent||21. "Joking Victim":||Absent|
|9. "Tiger Millionaire":||Absent||22. "Steven and the Stevens":||Absent|
|10. "Steven's Lion":||Absent||23. "Monster Buddies":||Absent|
|11. "Arcade Mania":||Absent||24. "An Indirect Kiss":||Absent|
|12. "Giant Woman":||Absent||25. "Mirror Gem":||Absent|
|13. "So Many Birthdays":||Absent||26. "Ocean Gem":||Absent|
|27. "House Guest":||Absent||40. "On the Run":||Absent|
|28. "Space Race":||Absent||41. "Horror Club":||Absent|
|29. "Secret Team":||Absent||42. "Winter Forecast":||Absent|
|30. "Island Adventure":||Absent||43. "Maximum Capacity":||Absent|
|31. "Keep Beach City Weird":||Absent||44. "Marble Madness":||Absent|
|32. "Fusion Cuisine":||Absent||45. "Rose's Scabbard":||Absent|
|33. "Garnet's Universe":||Absent||46. "Open Book":||Absent|
|34. "Watermelon Steven":||Absent||47. "Shirt Club":||Absent|
|35. "Lion 3: Straight to Video":||Absent||48. "Story for Steven":||Debut|
|36. "Warp Tour":||Absent||49. "The Message":||Absent|
|37. "Alone Together":||Absent||50. "Political Power":||Absent|
|38. "The Test":||Absent||51. "The Return":||Absent|
|39. "Future Vision":||Absent||52. "Jail Break":||Absent|
|1. "Full Disclosure":||Absent||14. "Historical Friction":||Absent|
|2. "Joy Ride":||Absent||15. "Friend Ship":||Absent|
|3. "Say Uncle":||Absent||16. "Nightmare Hospital":||Absent|
|4. "Love Letters":||Absent||17. "Sadie's Song":||Absent|
|5. "Reformed":||Absent||18. "Catch and Release":||Absent|
|6. "Sworn to the Sword":||Absent||19. "When It Rains":||Absent|
|7. "Rising Tides, Crashing Skies":||Absent||20. "Back to the Barn":||Absent|
|8. "Keeping It Together":||Absent||21. "Too Far":||Absent|
|9. "We Need to Talk":||Absent||22. "The Answer":||Absent|
|10. "Chille Tid":||Absent||23. "Steven's Birthday":||Absent|
|11. "Cry for Help":||Absent||24. "It Could've Been Great":||Absent|
|12. "Keystone Motel":||Absent||25. "Message Received":||Absent|
|13. "Onion Friend":||Mentioned||26. "Log Date 7 15 2":||Absent|
|1. "Super Watermelon Island":||Absent||13. "Kiki's Pizza Delivery Service":||Absent|
|2. "Gem Drill":||Absent||14. "Monster Reunion":||Absent|
|3. "Same Old World":||Absent||15. "Alone at Sea":||Absent|
|4. "Barn Mates":||Absent||16. "Greg the Babysitter":||Absent|
|5. "Hit the Diamond":||Absent||17. "Gem Hunt":||Absent|
|6. "Steven Floats":||Absent||18. "Crack the Whip":||Absent|
|7. "Drop Beat Dad":||Appears||19. "Steven vs. Amethyst":||Absent|
|8. "Mr. Greg":||Video & Mentioned||20/21. "Bismuth":||Absent|
|9. "Too Short to Ride":||Absent||22. "Beta":||Absent|
|10. "The New Lars":||Absent||23. "Earthlings":||Absent|
|11. "Beach City Drift":||Absent||24. "Back to the Moon":||Absent|
|12. "Restaurant Wars":||Absent||25. "Bubbled":||Absent|
Marty was Greg's greedy manager, taking 75% of the profits. He was also very condescending to Greg, constantly berating and insulting him. He did not even try to hide the fact that he was just using him. At the end of the episode, Greg is finally fed-up with Marty and chooses Rose over him, kicking Marty out of his van.
According to Greg, Marty is "dead to him". He does, however, admit that if it weren't for Marty, he would not have had the chance to meet Rose; so at the end of the episode he puts up a picture of himself and Marty on the shelf in his van that also holds other meaningful photos. Despite saying Marty was dead to him, when Marty later returned to Beach City, Greg was polite to him, even when Marty acted dismissive and looked down on Greg's job as a car wash owner.
Vidalia hooks-up with him as Greg is playing in Beach City. They attended a party with her friends together. Their relationship seems to have not been anything serious but rather a cheap fling, as Marty is quick to abandon her when he and Greg have to leave Beach City to continue the tour—which is a stark contrast to how Greg felt towards Rose. It's confirmed in "Onion Friend" that he is Sour Cream's father.
Sour Cream is Marty and Vidalia's son. He and his mother were later abandoned by Marty.
Sour Cream seems to trust Marty during his return, and eagerly follows his every command. Later on, when it's revealed that Marty has been using Sour Cream to advertise Guacola in Beach City, Sour Cream yells at him in the same language as Yellowtail and Onion, along with English.
Steven is seen to have an immediate disliking towards Marty, as Greg had told Steven about their history. When Marty first arrives in Beach City, Steven is ready to protect Greg before being calmed down. He later warms up to Marty after he makes him an official roadie, but his opinion quickly sours again after he sees he'd been exploiting Sour Cream to advertise Guacola.
- Marty's shoes in his current appearance resemble these Adidas shoes.
- In "Onion Friend", it is revealed that Amethyst doesn't think too highly of him, as she refers to him as "Farty Marty".
- It is unknown how Amethyst is aware of him, although Vidalia likely informed her.