This blood-stained spray features Lucy, a character from the anime known as Elfen Lied. You can use this in Team Fortress 2 and other games which support imported sprays.
Download the VTF to use it in-game: [link]
The base image was from the official art of Lucy found here: [link]
(Danbooru link, may also contain NSFW content.)
Elfen Lied (C) ADV Films, VAP (Japan)