JL Marlor (she/they) is a Brooklyn-based multidisciplinary artist, composer, electric guitarist, songwriter, and educator whose work "churns with fury" (The Washington Post) blurs the boundaries between the personal and political, the collective and individual, and the classical and contemporary. Known for their narrative-driven chamber music, opera, and vocal works, JL’s music draws deeply from Slavic women’s vocal traditions, riot grrrl punk, plainchant, and American protest music. Their work has been performed by ensembles such as Protestra, West Edge Opera, JACK Quartet, Wet Ink Ensemble, and LoftOpera, and commissioned by Washington National Opera, American Opera Projects, Teatro Grattacielo, Spark Duo, Chromic Duo, the DaCamera Singers, and many others.

In January 2025, JL debuted her fourth opera, Cry, Wolf (librettist, Clare Fuyuko Bierman,) at the Kennedy Center with the Washington National Opera. JL's fifth opera, Undone (librettist: Melisa Tien)  a commission from American Opera Project's Composers and the Voice program, will premiered in May 2025.

Beyond her classical compositions, JL fronts the indie rock band Tenderheart Bitches, hailed as "arriving on the indie rock scene with something serious to say" (The Wild Honeypie) and included in Them’s list of best new songs by queer artists. Their debut EP High Kicks channels themes of rage, catharsis, and radical femininity, echoing JL’s punk-inspired ethos. JL is also credited as a songwriter and arranger for Seonjae Kim’s riot grrrl adaptation of Antigone, Riot Antigone, which premiered at La MaMa and had its off-Broadway run at Ars Nova.