Lore

Kei is an A.I. made by aliens using the consciousness of an abducted human, now located in area 51 after she crashed the ship (possibly because of a payload) that ended up being discovered by the Governement.
She was placed in Area 51 which is basically SCP Foundation. She did not know why she was made, but she soon had urges to consume human flesh.
Researchers have discovered that she can travel through wired/wireless connections and can access and manipulate data on devices. They also know she retains some of her former identity to a certain extent and can sometimes access former memories, and she desires to be able to blend in with human/humanoid civilization.
Unbeknownst to them, she is contacting the outside world as a vtuber and gradually learning how to blend in; she also practices living in the outside in a virtual "infinite mansion" she made for herself and her pets (viruses she's kept contained for company). She isn't actually bound to devices; She can escape, though in a radically different form, and even eat and drink. The form she takes has been compared to a grotesque angel of death.
Hacking into Area 51's files, she discovers she wasn't created by aliens at all but archangels. The rapture happened quietly, but those who were taken were not those bound for heaven, it was those who had it in them to kill; these people were made into these "AI"s, and they are meant to kill all of humanity by accessing them through their devices. With the help of Seraph whom she met online, Kei Iris escapes and attempts to live a normal life without drawing attention and hopefully without consuming anyone.

Misc

-If humanity goes extinct, Kei Iris and all other AIs like her will die. This is the only way to truly kill them.
-She stays with Seraph in Purgatorio, which is similar to what humans would call "the hood", and uses a realistic human robot body to go out into society.
-Their dog, Beelzebub, is a three headed pit bull.
-Thinking pink is Kei's favorite color is an easy mistake to make, it's actually aqua.
-Kei has autism as an AI just like she did as a human.

Virus pets

TBD maybe.