Brook Soso (Kimiko Glenn) is an inmate at Litchfield Penitentiary on the Netflix series Orange is The New Black.
Brook ends up at Litchfield for protesting logging by living in a tree. Through her flashbacks, you learn that she has a long history of being an activist. She is shown going door to door, campaigning against the Walmart corporation with her bitter ex-boyfriend and her current crush.
Once in Litchfield, Nicky seduces Brook, and Brook reveals that it is not her first time having sex with a woman. Later, she develops a relationship with Poussey.
At first, she is hesitant to be open about her romantic relationship with Poussey because she had imagined a heterosexual future for herself. With time, however, she becomes more comfortable with her sexuality. She is devastated by Poussey's death and mourns her for the remainder of her time at Litchfield.
At the end of season 7, Sankey shares a Haiku she wrote for her, hinting at feelings she might have towards her.