Rosianna Halse Rojas (born 15 August 1991) is a British writer, video blogger, social media manager, and online personality.

She is best known for working with vlogger and novelist John Green, initially as his personal assistant, later producing partner.

[7] She would later pursue a Master of Science in Migration, Mobility and Development at SOAS University of London, completing her dissertation in 2022.

[9] On the account, she would post vlogs about Harry Potter, intellectualism and her personal school life as she studied for GCSE and A Level exams, among other topics.

[21] Regarding Life's Library, Rojas has stated: After the first year we’ve seen a brilliant and engaged community on the Discord, with thoughtful discussions about each of the titles and an excitement and curiosity about finding out more about the text, authors, and similar books.

All profits from Life's Library were donated to Partners in Health Sierra Leone to help reduce maternal mortality.

[24] Rojas also produces the podcasts The Anthropocene Reviewed and Dear Hank & John, both being co-productions of Complexly and WNYC Studios.

[26] Their currently unnamed production company is working with Fox 2000 to produce a film about AFC Wimbledon, a third-tier English soccer team.