If Akira is doing her business in the house, then she is leaving her scent / markings all over the house.
This claims it as HERS.
Brenin is attempting to reclaim the house by marking over Akiras scent.
When you can get Akira fully housebroken then Brenin should stop.
Also If Brenin is ALPHA, the Alpha dog marks over the top of others scent in the pack.
So that if a predator is tracking the pack by scent, it will be drawn to the strongest member of the pack.
Brenin won't differentiate between outside and inside, it's a natural protective instinct.