Marc is a drummer in the band Black Radly. He also serves as the band's manager. His cousin, Drew Protestant, is a spirit-talker who lent Marc a Terran book called "Luck in the Shadows," in which there was a special variety of bow called a "Black Radly," which everyone in the group (after Marc lent them the book Drew had lent him) thought sounded like a cool name for a band. And so, that's what they chose to name theirs. Drew also provides lyrics to various alien songs, which he receives from one of his spirit friends. While the band performs some of these songs, mostly the four of them collaborate on writing their own original songs. Aside from Marc's relationship with his cousin being of use to the band, Marc himself got them their first paying gig, in 912. They were hired by his aunt and her husband, George Taverner, the proprietors of a tavern called the Boar & Bear. Since that time, he has proven to be just as good at getting them both gigs and recording deals, with people who whom he is not related.
Because there are two guys and two girls in the band, and one of the guys (Jae Furthingtame) is dating one of the girls (Anja Frontrun), there has been occasional fan speculation about Marc possibly dating the other girl in the group, Rain W. However, the two of them insist they are just friends.
Marc's birthday falls on "Coming's End Day" (see Holidays of the Land).