Since debuting in 2015 with the play The Safe Family, she has continued to work across a wide range of media, moving between stage and screen. She has portrayed characters with nuanced depth in productions such as 99% Genius Diary, The Silence and the Noise, Dhobiwala, Cookie, Ann, Cream, and Young-ji. She has also appeared in television series including Yumi’s Cells 3 and The Price of Confession.
Since 2023, Sein Park and Juyoung Kwon have co-founded and run the play-specialized bookstore Inscript, where they share with readers the process through which texts come to life on stage. Alongside her work as an actor, she is expanding her practice as a cultural producer, engaging wider audiences through various programs and encounters, and broadening access to the world of playwriting.