Alyssa Sandra Marek was born on June 25, 1997 in Houston, Texas. Her theatrical experience began in performance gymnastics with the Show Team of Houston. She attended the University of Houston School of Theatre & Dance where she trained in classical acting. After graduating, Marek co-founded an all-female led media production company called Says Who? Productions with her three other classmates that is dedicated to engaging and uplifting the arts community in her native Houston.

Marek began voicing many characters for Sentai Filmworks (formerly ADV Films) by 2018 and one of her major roles starred is Ruby Hoshino in Oshi no Ko, another work by the author of Kaguya-sama: Love is War.