Sirius is a Pro Hero working on the Oki Mariner under Captain Selkie. Sirius is a young woman with smart blue eyes, sloping inwards, and short, shoulder-length hair of a lighter blue color which she wears side swept to the right. Sirius appears to be a generally friendly individual who was keen on teaching Tsuyu Asui the importance of becoming a hero. She is highly respectful of her Captain, although she is constantly embarrassed by his attempts to look cute. Sirius is selfless and would have rather been killed by Innsmouth than allow him to escape.