Long, long ago, Gensokyo was different. Prominent humans and youkai like Reimu Hakurei, Marisa Kirisame, Alice Margatroid, and Yukari Yakumo looked and acted different. This is when ZUN first came to Gensokyo to make the first Touhou games. But then something happened, after the five game was made. A terrible youkai incident happened, almost all of Gensokyo was destroyed and Reimu was almost killed. Yukari Yakumo, whose powers enabled her to manipulate boundaries and borders, was aided by Reimu to seal away this Gensokyo and start a new timeline, an alternate Gensokyo. So everybody's memories were wiped out and those who were either responsible for what had happened or were in hiding, were forgotten and left behind. Gensokyo would never be the same.
One of the youkai left behind was Mima. She wandered the wasteland hoping to see Marisa, whom she had a relationship, or see Reimu, her adversary. Even ZUN forgot about her, as he was making new games about events in the new Gensokyo.
She lived in near isolation until Yukari returned. Yukari made an offer to her to come into the Gensokyo that almost everyone else lived in. She would see Marisa and Reimu again. When she came, the new Gensokyo was changing, the advent of the railway made travel for the humans safer and was a new source of income for Reimu and another shrine maiden Mima didn't know about, Sanae Kochiya. The two mikos fought each other, not with danmaku, but with made up festivals and ticket prices. Mima knew she had to get used to this Gensokyo, that was when she met Marisa for the first time in forever. The two quickly became friends and she even took Marisa out for a drink. However, Marisa's lover, Alice, was highly suspicious of her after an incident were a badly injured Marisa was left in a shed in Mayohiga railyard.
Now the akuryou and the magician, were on thin ice with each other, the beginnings of a youkai incident are apparent. With Marisa and Alice's relationship on the line, and Mima's reintroduction into Gensokyo being questioned. Something was going to give.
