The story revolves around a scarlet mist appearing without warning in Gensokyo, covering the sky. The heroines find themselves at the Scarlet Devil Mansion as they seek out the culprit.
Eternal Shrine MaidenReimu Hakurei
Shrine maiden of the Hakurei Shrine.
She appears quite carefree on the outside, and indeed deep down, she really is carefree.
She lives in her shrine and is rarely visited by anyone, which causes her to be out of touch with current social norms.
The Strange MagicianMarisa Kirisame
A girl who lives in isolation from other people, as is the fate of a magician.
Basically, her wits are sharp, but she generally does not make the best use of them in her daily life.
Youkai of the DuskRumia
Stage 1 Boss
A youkai with no importance to the story, and isn't up to anything in particular in her life.
The ribbon tied to her hair is actually a charm; she can't touch it even though there have been times when she wanted to take it off.
Ice Fairy of the LakeCirno
Stage 2 Boss
A girl of snow. Her intellect is not very developed. She's just a child.
To Reimu and Marisa, she can be easily defeated. She likes playing tricks and often toys with frogs. She freezes them instantly, then watches them revive as they thaw in the water.
Chinese GirlHong Meiling
Stage 3 Boss
A Chinese-looking youkai. Her clothing is colorful and somewhat traditional.
She is the gatekeeper of the Scarlet Devil Mansion, and prevents intruders from beyond the lake from reaching the mansion.
The Girl of Knowledge and ShadePatchouli Knowledge
Stage 4 Boss
A witch who has lived for 100 years.
Her weak constitution makes her poor at physical combat, but she makes up for for that with her various and powerful magical attacks.
Maid of the Scarlet Devil MansionSakuya Izayoi
Stage 5 Boss
Her time manipulation distances her from the human race. She has given up trying to be friendly to ordinary people.
She does not care about honor or power; she thinks so long as it earns her dinner, being the Scarlet Devil Mansion's maid is fine.
The Eternally Young Scarlet MoonRemilia Scarlet
Final Boss
She is a vampire. She blanketed Gensokyo with a magic mist in order to cut off the sunlight.
Although she has been alive for 500 years, her personality is that of a selfish child.
Sister of the DevilFlandre Scarlet
Extra Stage Boss
She is a vampiric magical girl and has been the Scarlet Devil's younger sister for about 495 years.
She cannot control herself, so generally she isn't let outside.
She also doesn't try going out.
