東方全員吸血鬼

Remilia turns Sakuya into a vampire, and everything just goes to hell from there.

It was started by supon, with this pixiv page explaining the rules:
◆Outline
Let's turn all the Touhou characters into vampires and draw pictures of them draining or being drained of their blood!

◆Story So Far
1. Remilia appears to have gotten serious.
Right now → 2. All Touhou characters become vampires!
3. When morning comes, everyone returns to normal and the incident is resolved.

◆Rules
•All participants please use the "All-Vampire Touhou" tag.
•As the project is rated R-18G, please set all participating works to R-18G, regardless of content.
•There doesn't have to be any particular story, though there is continuity between some of the planner's and/or participants' images. Please approach this without regard to changes in backstory or people acting out of character.

◆Must-haves
•Suck blood from anyone—youkai, dolls, ghosts, gods! Turn everyone into vampires!!
•Vampiric acts are as erotic as sexual acts! (pant pant)
•Take it easy on the teen angst/emo stuff.

Here are some of the responses.