Musse's goal was to build back the Noble Faction to act as a counterweight to Osbourne after Cayenne was defeated in Cold Steel 2. She got in contact with Aurelia and Vita in the wake of her uncle's fall and gained their trust by displaying how intelligent she was, mostly by predicting certain outcomes (Aurelia being sent to North Ambria being one of them). The general consensus is that the Noble Faction would've fared much better in the Civil War if Musse was in charge instead of Cayenne.
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Bart, with $10,000, we'd be millionaires! We could buy all kinds of useful things like...love! ~Homer J. Simpson