As We Chase the Sun

After torturing the Longbottoms, Bellatrix Lestrange fakes her death to escape the Aurors. An unregistered Animagus, she continues her search for her master. But there is a reason that Animagus transformations are so dangerous. Isolated and without human contact, she loses herself. When Sirius discovers her in the Forbidden Forest, Dumbledore hatches a plan. Black family centric.