Sing me a river Marshall (gumlee, gumshall, marball)

Alternate universe where the characters are in the music business. Marshall and Gumball have known each other since highs school but now that they are idols of america, they grew apart. That all changes when suddenly Marshall changes music contracts transferring to gumball's organization and both of their respective bands sign to a reality competition show for artist that send them to, Paris, London, Tokyo and all over the world. Obstacles of epic proportions appear to tear the two apart. A gumlee/ Gumshall fanfic