Saya (Saya no Uta)

{Quote|"But...her voice when she's in pain is pretty adorable, you know?" |Saya}}

"Saya" is the name given to an extradimensional alien brought into this world the experiments of Dr. Ougai, a Japanese doctor working for the Tokyo University Hospital. Saya initially lived with Ougai, until she got loose in the hospital, feeding on cats, and eventually human infants. "Saya" met Fuminori Sakisaka in the hospital, who, because of brain damage from an accident, saw "Saya" as a normal girl, but saw everyone else as horrific monsters and everything as covered in blood and gore. Fuminori fell in love with Saya, and under her influence, discovered a taste for human flesh. Saya and Fuminori go onto kill several people including their neighbors and one of Fuminori's friends, a woman named Oumi Takahata. Saya is capable of modifying the DNA of any species she has samples of genetic material from, and can rearrange the cells of organisms, even transforming Yoh Tsukuba, another of Fuminori's friends, into one of her species. Saya is very resiliant, being able to survive multiple gunshots and other attacks, however, severe damage, such as having a large part of her body destroyed can kill her can kill "her". For the purposes of this wiki, this includes numerous gunshots or melee attacks, explosions, acid, flash freezing, burning, and other such injuries.

Depending on the ending, Saya either successfully transforms all of the human race into her species or is killed by Dr. Ryouko Tanbou, Fuminori's psychiatrist douses her in liquid nitrogen and shoots her with a sawed-off shotgun.