Okay, so I believe that I have finally evolved this idea to the point where it is greenlight-ready!

The SCP is a humanoid who can only exist if people remember her. She resides in a separate dimension, which is very, very bright if there are lots of people who know of her. However, the less people who do, the darker her realm becomes. When people do remember her, she can slightly influence their actions (usually using them to spread her image to others, spreading her reign). In order for her to be contained, one D-Class personnel is forced to remember her, and not interact with anyone else. The document containing her Special Containment Procedures is only accessible through one terminal. The terminal is contained within a sealed room, and after the terminal is shut off, amnestic gas is released. A body scanner and a guard are stationed in front to ensure no personnel enter the room with gas masks or other devices to filter out the amnestics.

Her Backstory Her Backstory So, the backstory for her is that she ruled over the city-state of Alagadda for a long while (she didn't form it in the first place, but she found it and gained control of it). She was fair and somewhat kind, but none of her subjects followed her of their own will. One of her subjects, unfortunately for her, was experimenting with magic, and shook off her control over him. He overthrew her by casting a spell causing everyone in the city to forget her, and he had every image of her destroyed (well, almost). Due to the nature of the spell, he could not forget her, though she could not control him. So she didn't die, but she was powerless. Eventually, the king is overthrown, causing the queen to begin to wither and die, and her realm to go completely dark. Eventually, just as the last of her essence was about to fade from existence, she begins to reform. A team of SCP agents sent into Alagadda found what might have been the only carving of her left, which instilled her into their minds. They went back to their Site and began to proselytize the queen, spreading her power further. She is back in power, and her realm glows once again. Then, high-powered amnestics are administered throughout the site to make everyone forget everything. The Foundation learns a bit about the queen and classifies her as an SCP. In order to contain her, they have one D-Class know her, and have them locked in a soundproof cell. No direct contact is allowed, and meals are administered using sort of an airlock type contraption (two doors with a little space in between them) to keep contamination risks at a minimum.

An Idea for a Tale An Idea for a Tale An interesting tale idea is "What if she breaks containment?", and that is something I want to explore. One day, the D-Class uses their meal to draw a picture of the queen on the wall. It's cleaned up quickly, but one of the scientists who was watching them stays infected even after amnestics are administered to everyone. The queen, having learned from her mistake during her last outbreak, buried herself deep within the scientist's brain, so the amnestics don't affect her. She stays dormant until the scientist goes home, at which point he draws a picture of the queen and photocopies it ~1,000 times. He sends them via mail to anyone he can, including many agents at the Site and the 05-Council. She successfully spreads throughout the world in a domino effect, even infecting most of the Council. It's a generally bad situation for everyone. Though she was once an actually alright ruler, now she is completely bent on finding the one who overthrew her and making him pay. A small group of uninfected agents, including a member of the 05-Council and MTF-Delta-11 (Forgetful Minds), an MTF specially trained for dealing with memetic hazards, go on a trip to Alagadda. There is a battle going on between the residents of Alagadda and infected SCP agents. The uninfected group have an audience with the Hanged King, asking for him to use the spell he used before on a much wider scale. He agrees, in exchange for the lives of all infected agents who entered the city. The group agrees, and they are all knocked out. When they wake up, they know nothing of what happened. All traces of the queen are expunged from everyone's minds, as well as statues, paintings, carvings, etc. of the queen disappearing. The only record of her is the document and the single D-Class still in containment. A report is filed about ~650 Foundation personnel who mysteriously disappeared, and the tale ends.

I'm thinking of explaining most of the backstory in an interview log with the D-Class containing her. The SCP article would focus on explaining her abilities and their limits as well. Anyway, let me know what you think! Again, greenlights appreciated!