Coltrane is a friend of Jeremy Johnson and a member of his band.
Coltrane is the bassist in his band, Jeremy and the Incidentals, and a love interest in Stacy Hirano. He, along with Jeremy and the band's unnamed drummer, performed at the Summer Festival, during which they were briefly transformed into a punk rock version of themselves by Dr. Doofenshmirtz's Ugly-inator. ("The Best Lazy Day Ever").
Coltrane appears to have a love interest for Stacy. While performing "Do Nothing Day", they can be seen smiling at each other similar to Candace and Jeremy's way of smiling at each other during the song ("The Best Lazy Day Ever").
The two later formally introduced themselves to each othеr during the "Summer Rocks!" concert. They immediately show mutual attraction to each other, including dancing with each other during "Gimme a Grade" and holding hands afterwards. He also said he would teach her to play bass ("The Baljeatles"). He called her in "Candace Gets Busted". They were later seen dancing together on New Year's Eve ("Happy New Year!"). In 2013, Swampy mentioned on Twitter that they were a couple, this was confirmed by Coltrane himself in "Mandace".
He is great friends with Jeremy Johnson. He may be like what Stacy is to Candace, a best friend. He is seen watching TV with Jeremy ("Let's Take a Quiz") and talking with Jeremy during the "Summer Rocks!" concert ("The Baljeatles"). He is also seen at Jeremy's party ("De Plane! De Plane!").
- In "The Best Lazy Day Ever" and "Let's Take a Quiz", Coltrane wore a red hat, t-shirt and shorts. His character layout and appearance was changed in "The Baljeatles" so that he would look more like his voice actor, Corbin Bleu. However, in "Make Play", "Candace Gets Busted" and "Mandace", he switches back to his original outfit.
- Corbin Bleu also was Ashley Tisdale's (who voices Candace) former movie co-star from the High School Musical series.
- Coltrane may have been named for the jazz saxophonist John Coltrane.
- He could possibly be Stacy’s future husband in Phineas and Ferb Quantum Boogaloo
- "The Best Lazy Day Ever"
- "De Plane! De Plane!" (Cameo)
- "Let's Take a Quiz" (Cameo)
- "The Baljeatles"
- "Phineas and Ferb: Summer Belongs to You!" (Cameo)
- "Make Play" (Cameo)
- "Candace Gets Busted"
- "Rollercoaster: The Musical!"
- "Run, Candace, Run (Cameo)
- "Happy New Year!"
- Phineas and Ferb The Movie: Candace Against the Universe (Cameo)