On a second thought, Sayo deciding to start presenting as a man on Rokkenjima of all places makes sense actually: they've been playing on Lunatic Difficulty since the day Genji and Kumasawa thought it was a good idea to throw a SIX year-old with no house work experience into that kind of highly demanding workplace, a kid who didn't know how to swim into a wave pool.
The more I reread Umineko, the more their characters come across as either incredibly near-sighted or deeply uncaring towards Sayo in the light of all the obstacles of their first years on Rokkenjima that were 100% predictable: -Sayo being ostracized due to the age and experience gap from their coworkers even had they been more patient, -Sayo being pushed towards befriending Jessica all while Natsuhi fighting back against that, -Sayo having difficulty tending any friendship made at school BECAUSE of their work schedule(this might have affected their grades too for years)
It was really never about what Sayo's well being or happiness at all.
