Nimesha is a vocal advocate for the LGBTQ+ community and has spearheaded various activities to increase public awareness of the community. In Sri Lanka, LGBTQ individuals are often viewed negatively, and LGBTQ-related stereotypes have often put individuals under vulnerability such as social rejection, public humiliation, and embarrassment.[4]
Nimesha had collaborated with the Janatha Vimukthi Peramuna for a brief period but eventually parted ways with the party due to creative differences with its policies.[4] In 2022, she took part in the Aragalaya protests against the government of then-incumbent president Gotabaya Rajapaksa.[6] She coordinated a Pride March as part of the protests at Galle Face, and under her guidance, the first pride parade was held in Sri Lanka. She and many other LGBTQ activists joined the Aragalaya movement and installed a tent on Galle Face, protesting alongside other protesters with a focus on LGBTQ issues.[4]
In 2024, Nimesha contested the parliamentary elections from the Kegalle District, representing the Socialist Party of Sri Lanka as one of the party's main candidates. Her campaign focused predominantly on tackling social justice issues. Although she was not elected, her campaign represented a significant step in transgender visibility in Sri Lanka.[5]