Time. A judge in their simplest form. It's always a race against Time here in-between missions, when we have nothing to do. . . We study Time. We expose her flaws & engineer newer ones to help us finish our missions as quickly as possible. Time is different in their world. Faster, we think. But - humans' die fast in our realm as well. We aren't for certain.
Time dislikes those who trick her, so she plays tricks upon them in turn. We've all woken up in the wrong dimension, or have encountered deja vu. This is Time's doing. She isn't spiteful, but she dislikes rule breakers. Those who test her are dealt with severely. Some are even forced to live in the Gendu, the human realm.
Time can not be destroyed. She can not be recreated. Technically, she doesn't even exist. But she's there; egging us all on. Hurtling us into the ever present future, barely allowing us to study our past... our own history.
She guides us. We live by her laws. Our lives center around her. She is a Goddess.
And we are her assassins.