Yassen Grigorov lives in Sofia, where he works as an illustrator, painter, and filmmaker. He graduated from the National Academy of Art in Sofia, the École supérieure d’Arts Appliqués in Geneva, L’École européenne supérieure de l’image in Angouleme, France, and the National Academy of Theatre and Film Art, Sofia, where he studied cinema and television directing. He is a feature film director with experience in documentary and television. As an illustrator, Grigorov has published over 60 books for various publishing houses. They have brought him international recognition and awards, and have been translated into French, Spanish, and Korean. Among them are How Many Strawberries Grow by the Sea, 2016, and Les Angesgardiens (Joie de lire, 2001). 

Grigorov was awarded a Special Diploma from the Bologna Ragazzi Children’s Book Festival, 2002, and he is a winner of the French Prix Octogones for children’s literature, 2004, as well as of the Award of the Union of Bulgarian Film Critics, 2011. His book If I Were a Colour (Tochitsa, 2021) was included in the White Ravens catalogue, 2022. He received the Konstantin Konstantinov National Award for Illustration for his work on Sweet Pet Mosquito (Tochitsa, 2025).