Part of me wants to say that Dangereuse was an alias. Dangereuse was a 'muse' to
William the Troubadour
Duke of Aquitaine. If I remember my medieval history correctly, the troubadours wrote mainly to try to get the 'muse' into their bed. If that is true,
Aenor might have married her half brother.
But, I'm also descended from a bastard son of
John of England and his cousin
Adele.
Adele's dad was the bastard son of
Geoffrey Plantagenet,
John's paternal grandfather.