|“||The moon tonight is red. You will know death.||„|
|~ Remilia Scarlet|
Remilia Scarlet is the owner and head of the Scarlet Devil Mansion from the Touhou Project series of video games, the mistress of Sakuya and Meiling, and the older sister (and guardian) of Flandre. Though her appearance (and often behavior) is childlike and seems nonthreatening, she has fearsome magical powers and a reputation to match, being known throughout Gensokyo as the dangerous "Scarlet Devil." Like all vampires she is photosensitive and weakens when exposed to sunlight, so she typically remains inside her mansion (which has few windows to prevent light getting in) during the day and emerges during the night. While she is naturally known to drink human blood, her light appetite means her victims almost never die from their wounds.
In Embodiment of Scarlet Devil, Remilia decided to release a mist over Gensokyo to block out the sun and let her move freely during the day; after her scheme was discovered and halted, she was forced to use a parasol to shade herself when she wanted to move around during daylight hours (as mentioned in Immaterial and Missing Power). In Imperishable Night she headed out to punish the ones who took the full moon from the night sky since the fighting would be at night. In Scarlet Weather Rhapsody, she settles her "own" investigation by ordering Sakuya to drag the suspects to her, in order to find the culprit, figuring later that the culprit is above the mountains, where she is very prone to the light.
While her behavior is usually self-centered and somewhat bratty, it is possible to befriend her, however, humans and youkai alike prefer to avoid her. Her name, appearance, house, and clothing all indicate she is European in origin and emigrated to Japan many years ago (Her reason is unknown). She claims to be a descendant of the world's most notorious vampire, Count Vlad Ţepeş Dracul, but this is a bald-faced lie.
- Her red eyes, short light-blue hair, pair of black bat-like wings on back. Wears a pink mob cap and dress, with bright red trimming. Noticeably short.
- In Touhou 7.5 and 10.5, alternate outfit (Palette) Dress is red instead of pink and her hair is also blonde. This color scheme seems vaguely familiar...
- In Touhou 6, 7.5 and 10.5 same as above, but she wears a necklace featuring something like Caduceus.
While she tries to cultivate the image of a mysterious and frightening vampire aristocrat, Remilia is as childish as her appearance suggests. Her long lifetime has only served to make her grow bored more quickly, and she prizes anything she finds novel. In Silent Sinner in Blue she allows herself to be manipulated by Yukari Yakumo, simply because the alternative would be boring. The other residents of the Scarlet Devil Mansion spend much of their time catering to Remilia's odd whims (including numerous parties), but she appreciates their efforts and treats them with respect.
- Flandre Scarlet (Younger sister)
- Patchouli Knowledge (Friend)
- Sakuya Izayoi (Chief maid)
- Hong Meiling (Gatekeeper)
- Koakuma (Unknown)
- Due to "The Young Descendant of Tepes", the title of the prelude theme to the final boss stage of Embodiment of Scarlet Devil, she has been sometimes linked to Count Dracula's lineage. This is because Dracula's full name is Vlad Ţepeş Dracul. While Remilia herself asserts that she is a literal descendant of Ţepeş, ZUN claims that she is lying.
- Like most vampires, Remilia has the power of shapeshifting at her disposal and can change into a bat. However, unlike most vampires, her wings remain visible even when she is in human form, making it impossible to pass herself off completely as a human.
- Remilia is not only Sakuya Izayoi's master but the one who gave Sakuya her name, according to Perfect Memento in Strict Sense. Considering Sakuya's murky past and the unlikelihood of a human becoming a vampire's servant, the leading theory is that Sakuya was once a vampire hunter, and Remilia earned Sakuya's servitude by besting her in combat.
- According to Gensokyo's timeline, Remilia was born in the year 1503, making her, as well as Flandre Scarlet, two of very few characters whose birth dates are actually known.
- One of Remilia's spell card is named after Gungnir, the spear of Odin described as having the ability to always hit its mark.
- It is quite coincidental that Remilia's appearance was in the 6th game of the Touhou Project. She is the Stage 6 boss, and the player will fight through 6 spell cards on that stage on any playable difficulty above Easy (Remilia has 5 spell cards total and Sakuya has 1 in her midboss appearance). When these numbers are all put together, it reads "666", best known as the "number of the beast".
- In "Touhou Hisoutensoku", if the player places a custom parasol system card in Remilia's deck, she'll be able to fight in stages that has sunlight, although she isn't shown with a parasol on-screen.
- Remilia's theme starts the same as Beethoven's Piano Sonata no.8 Pathetique, "3rd Movement".
- In Curiosities of Lotus Asia Chapter 4, Reimu Hakurei comments that Remilia should go back to her coffin. Remilia retorts that coffins are for the dead, indicating that she doesn't sleep in a coffin. In Imperishable Night's Scarlet Team Scenario, before battling Reimu, Remilia once again reminds her that she doesn't sleep in a coffin. Finally, in Oriental Sacred Place Chapter 15, released 7 years later, what's apparently the first canonical depiction of Remilia's bedroom is shown, and that she sleeps in a coffin (on a bed).
- Her first five alternate pallets in Touhou Hisoutensoku resemble Flandre Scarlet, Patchouli Knowledge, Hong Meiling, Sakuya Izayoi and Koakuma, respectively.
- Despite her childish-girly appearance, she uses both a haughty "mistress"(～かしら？、～だわ) and a strong manly（～か？、～だ） speech patterns in her original Japanese lines. Unfortunately most of these nuances cannot be translated into English.