This is how the dynamic tended to be like between Cipher and Tillie when she was a henchmaniac. He named her "The Devil" and liked to ragebait and stress her.
The only reason he wouldn't kill her is because her rage was too entertaining.
She went insane trying to protect her children, the gems, from Cipher.
She is cruel and rash and highly reactive. She tries to hurt people before they hurt her.
With her children she is protective and tries her best to be still and loving, although she may falter at times.
She is a product of her situation of being a henchmaniac of Cipher's while she had these children.
They're all hers, she's the only parent.
She and her children have died dozens of times.
The Devil restarts the timeline and tries to survive with them all again and again, effectively trapping herself and her children in a timeloop.
The children love their mama and trust her.
The Gems were forced to evolve from the harsh conditions and the constant reincarnations.
They had gone through things ranging from not having enough food to Cipher finding out about them and toying with them until they died one by one.
Azurite, the one with the red heart, tends to be the first to die. She is the most colorful and playful one, mistaking Cipher as a friend.
In the "best" timeline, Azurite is the only Gem to pass away. This, of course, isn't good enough for The Devil but The Axolotl tries to convince her to not sacrifice what goodness she was able to promise her other children.
The Devil met The Axolotl after the Time Police raided the nightmare realm and Time Baby killed her in retaliation after learning she had eaten and "killed" the only other Time Titan left before Time Baby.
The Oracle prayed to Xolotl because the children didn't have their mother and The Oracle needed guidance.
Xolotl took them in along with The Devil's soul to try and help rehabilitate them in the Theraprism.
The Devil is a very intense patient, using her ability to see timelines against anyone that gets close. She uses peoples biggest shames, secrets and griefs agaisnt them as a defense mechanism.
Heres all the Gems in their full color
Xolotl learned that she is only calm when she is around her children. They take this opportunity to try and get closer to her and help her from the angle of a friend and second caretaker of The Gems.
From top left to right:
Azurite
Perla
Moonstone
Larimar
Selenite
Jade
Theres many more details but this is long as it is.
Theyre all based on different kinds of sea angels.