Everything Painted Scarlet

History

Originally, I was born into a female human body, along with Koru who was my sister at the time. We do not remember being human much, but it was not for very long regardless as we were both unwanted children born as an unwanted pregnancy. We do not remember why, but I would assume our mother was raped, and so she hated us, as did her new partner.
They had little money to support us, and used us for chores primarily, but eventually even that was not payment enough for our existence and they decided it would be more cost effective to kill us while we were still young. We had never been allowed to leave the house, no one locally likely even knew we existed, and we were killed as one of the many child deaths of the era without so much as a gravestone to mark us.However, we were reanimated in the small boxes we were crammed into in the garden under a tree, as vampires. We clawed our way out, and killed the ones who killed us.
We had become vengeful spirits, which had possessed our previous bodies and sought revenge.
However we also sought to kill the one who raped our mother as well, who had been far wealthier and lived in a mansion. We killed all those who lived there as well, and news spread immediately. No one found us during the day, but anyone who stayed the night would end up dead by morning, and the building was considered 'haunted' and abandoned. Now, it was ours, and dubbed The Scarlet Devil Mansion, due to how bloody the murders had been and discovered by authorities the next day.Many years passed, and no one dared to come close to the mansion any more due to it now becoming common knowledge that it was haunted by vampires. However one was drawn to us by the tales instead. He considered himself to be a vampire hunter of sorts, and came to us in search of us to challenge us.
I confronted him quickly as soon as he entered and subdued him, to which he fell to his knees and instead asked to serve me instead. Enough time had passed that I had calmed and developed enough to start questioning myself and who and what I was, and the offer this human presented me to teach me about the world was intriguing, so I accepted it.This human was a cismale version of Sakuya Izayoi, however over time he frequently showed an interest in being my maid, and would become aroused at my harsh treatment of him. Flan would also join in on occasion, though more because they enjoyed 'being involved', without really understanding what was happening.A short time passed like this, and others slowly added to our small family, though we barely remember them by now. But we assume this is when we met Patcholi and Koakuma.
However, one day something happened. We are not sure what triggered it, but we are aware that Flan caused a threat to the world that was far more vast than simply haunting our mansion, rather it endangered thousands of human's lives. It would not be an understatement to call it a small apocalyptic event.
This, gained the attention of those who monitored Gensokyo.
Those who lived there saw us as too great a threat to live in the human realm, and so Yukari Yakumo instead forcibly relocated us to Gensokyo, mansion and all. We were also threatened to behave, and so Flan was also condemned to hundreds of years within the basement for this endangerment not just to humans, but to other yokai as well.From this point I was angry that they had forced my sister to be locked up, but maintained it only so I could work on ways to allow us to dominate the realm and overthrow those in power so we might be free once more.I do not remember specifically creating a mist, as shown in canon, but I do know I was unhappy with being treated as I had been and ended up inconveniencing the other inhabitance somehow. This tempted Reimu and Marisa to come to our Mansion in their pursuit of preventing it.Marisa found Flan in the basement and convinced her to talk to me about how unhappy she was. This, while trying to avoid being exploded, and bitten, repeatedly.
Flan came to me with Marisa, and I was disgusted to see Flan being brainwashed by a human and attacked Marisa. Long story short, we were eventually subdued, my hold over the world lessened and we gradually found our place within Gensokyo as Flan wished to befriend everyone, excited to be out of the basement. Though it was not easy, as Flan had not been spending the time learning that I had, and it caused many issues and misunderstandings.Despite a promising start, we do not believe our attempts to 'make friends' were terribly successful, and soon we were left alone again.

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