Flandre is the younger sister of Remilia and the "dirty little secret" of Scarlet Devil Mansion. Because of her unstable personality and incredible destructive power, her sister has ordered her not to leave the mansion for nearly 500 years. She really respects her older sister Remilia, but her raw destructive power far exceeds that of her sister's. Although she is usually docile, her insanity makes it difficult for others to understand her.When vampires attack humans, they generally try to take their prey alive in order to suck its blood afterward, but Flandre has always been fed with cooked dishes, and thus doesn't know how to properly attack a human. Whenever she tries to attack a human, she loses control of herself and blows them away without leaving a spot of blood. Her apparent age is about the same as Remilia Scarlet (who looks to be around 10, even though Remilia is 5 years older and they're both about 500 years old). Flandre can destroy anything she wants by moving the "eye" of the object, where the tension is highest, into her hand and pouring her power into it. When she clenches her fist whatever she has moved the "eye" of into her hand will be destroyed.  She also has extreme physical strength. Unsurprisingly, all the toys she plays with get broken. Flandre's wings have an unusual appearance which bear almost no resemblance to a vampire's typical bat-like wings (or even organic matter). It has been speculated that her wings are artificial and that she fashioned them herself and then attached them to her body. She may have lost her original wings or been born without them. 

A collaboration anime project of Anime Tenchou and Touhou animated by ufotable. The anime was shown at the 2010 Animate Ichioshi Bishojo Anime Matsuri.

The second in the line of official Touhou Spell Card printworks, featuring a traditional comic story drawn by Aya Azuma and a danmaku fireworks competition that takes a wrong turn right in the middle.

Touhou Chireikiden focuses on Satori Komeiji's endeavors as a detective, solving mysteries around Gensokyo.

Based on characters from the Touhou Project series. 
Koumakan is a Western-style mansion by the lake with few windows. The house is inhabited by a vampire master and a group of beautiful women, each with her own unique personality.
 
(Source: ComicWalker, translated)

Based on characters from the Touhou Project series. 
A new serialization has begun for a story brimming with emotion and lingering impressions that offers a glimpse into the casual interactions of fantasy girls.
 
(Source: Kadokawa, translated)

Flandre Scarlet