What is known
S44Opposed the betrothal, as Soshi Aisha let slip — which is the thread Setsuna is pulling on when she names the Scorpion as the hidden party.
S47The Emperor's advisor. Was in line to lead the Shosuro until marriage to Bayushi Shoju made her Bayushi; some Scorpion still think that was a mistake. Her husband is Champion of the clan and untroubled by her standing with the throne. The Emperor's sight is failing and she reads his correspondence to him, which means she decides what reaches him — and she is exactly the sort of person who could dispatch an envoy. Setsuna's own mentor once used one of her manoeuvres as a lesson: perfectly within Imperial law, entirely against its spirit.