Somehow I have a feeling that Aria anticipated something to happen and prepared counter-measures in advance. She's had connections to the Rainfords for centuries and should have witnessed that tradition because it was carried out in the past... in that case, whatever they may try would probably fail. Hard.
Regarding the situation at the end... had it been me, I would have summoned
Poly Agnes after that cut off duel and let her guard my room, maybe even the bath. She could handle an intrusive b!tch or two. At least it would make them speechless, I guess.