Long-suffering Italian classical music accompanist and friend of classical violinist Ulrico Antonio from the convoluted "The Violin of Death!" story of comic book Weird Horrors #2 (Aug. 1952). Antonio's career is in a slump, and he's convinced owning a Stradivarius violin will fix all his problems. Overheard by a weird blind beggar who promises Antonio a Strad, they follow him back to his creepy cottage. Antonio says he'd give his soul for a Stradivarius, the beggar lets him play the Strad, shadowy figures begin to appear, the place catches on fire, and the beggar AND the cottage disappear, poof, along with the violin.
Poor Monti has to suffer through Antonio's ever-bizarre compulsions to get a Strad, and even unwittingly helps him perform necromancy to do so.
When Antonio goes blind, and is compelled to travel to Genoa, Monti helps him, only to see Antonio lure another, unnamed, concert violinist into the vicious circle of black magic with promises of a Stradivarius.
It is never indicated what instrument Monti plays.