Riftmaster

Master of the Rift, unaffected by Abyssal Absorption, creator of the Realms and the Gift

Lily

Their powers are limited to the Rift, not including the Realms the Nihilitree links together

Immune to Abyssal Absorption / [[Condition-2005]]

Granted each Realm a Gift at different points in time, causing them to change in different ways

No family

They fell into the void not long after gaining sentience, becoming the ruler of it for being the first to find it
Bored with their new existence, they started experimenting with what they could do, and they created worlds
They decided to grant a Gift to each world, sharing it at different points of time to see what would change
This is how the Realms became what they are today

The Deity page of Riftmaster