Children's engagement with Japanese toys and fictional characters has taken on new significance in the age of YouTube. Drawing on ethnographic research on technology-mediated play among 8- and 9-year-olds in Norway, this article shows how boundaries between "real" humans and "fake" non-humans are blurred and undermined when children take on the perspective of a fictional pop star known as Miku. I argue that YouTube provides a platform for children's playful experimentation with posthuman subjectivities, where they orient themselves toward the future not in terms of becoming adult but in terms of multiple becomings.
Keywords: Animism; YouTube; becoming; cosplay; play.