Vult

"'Please don't worry, my children... All will be well.' - Vult to Leeren and Kuro"

The First Shadow - Origin
Vult, or as her creation name was, Darkin, was a female homunculus of Tael Xeno Licht tasked with keeping a strong bond with the Path of Darkness of the reincarnation loop. She was trained in her arts by the same, and slowly but surely developed romantic feelings towards her male counterpart, at the time named Monsoon. These feelings however, were not reciprocated, as Monsoon's only interest was in righteousness and justice, and he shunned any sort of romatic relationships towards him greatly, something he would change overtime.

Vult, as she began to call herself after she began living in the Torghast, the Tower at the Reverse Side of Caelum, has been ever since a motherly figure towards Kuro and Leeren, being the one that actually gifted him a name. Even though she was ultimately betrayed, she held no hard feelings against either Kuro and Leeren and in fact expected such to happen.