(Touhou 7 to 9) Dark blue eyes, silver hair, has a long braid on each side of the face, carries many knives. Wears a pink and dark blue French maid's outfit, and a pink bonnet on her head.
(Touhou 6) Same as above, except she had bright red eyes.
(Touhou 9, alternative outfit) Same as Touhou 7-9, but her outfit is mainly dark red instead of dark blue.
Since Sakuya has tremendous skill with handling knives, she is extremely good at cooking.
Sakuya "prepares" food for Remilia and Flandre Scarlet. It's a mystery how this is done exactly, although she mentions in Phantasmagoria of Flower View that with so many flowers around, she can make as much tea and as many pastries as she wants.
According to Sakuya, if she happens to run out of knives, she can freeze time and pick up the ones she threw previously.
According to ZUN, "Manipulation of Time" is synonymous to "Manipulation of Space". She takes advantage of this fact in several ways, from enlarging the space inside Scarlet Devil Mansion, to probably storing an immense amount of knives around. Maybe it's general relativity?
The characters for Izayoi literally mean "Sixteen-day-old moon", and Sakuya "Blossoming night."
Sakuya seems to have romantic feelings for Remillia.
In some pictures and comics, Sakuya is depicted as a dog.
5th stage boss. The maid is a human about 10~20 years old.
That power of hers distances her from the human race. She has given up trying to relate 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.
She is the chief of the Scarlet Devil Mansion's maids and cleaning staff, and always takes advantage of her ability to stop time when working.
(If she cleans up with time stopped, dust will not fly around)
Since the master of this house is her, the maids also serve as personal attendants.
The elegant maid of the mansion. Has the power of manipulating time.
Sharp and able, her only weakness is being unable to take hot food.
Since the practice of throwing knives is similar to that of cooking, Sakuya is very good at cooking.
Recently she is waiting for valuable ingredients to make Chinese food.
In addition, her knives are recycled after throwing to save money and the planet.
When she runs out of knives during a battle, she stops time and picks them all up again.
Throwing knives are her weapon. Deceitless sleight-of-hand is her pride.
Life as a maid is quite comfortable for her since she doesn't have to worry about clothing, food, or housing even though she lives very deep in the mountains.
She is sometimes hated by both humans and youkai because she lives and works for the Scarlet Devil. Nevertheless, she has friends who don't mind her employer and she doesn't need to worry about her living conditions. She can't imagine a life better than this.