Blood-C/WMG

Saya's Eye will never heal, is the price of a wish: to become capable of killing humans

• Jossed, by the last shot in the movie trailer after episode 12. Unless we're looking at a reflection, for some reason.

fumito will use saya`s blood for military purposes.

Saya is Saya from Blood Plus under a different last name.

This is hinted at by the brief flashes of what looks like her fighting Chiropterans.

The teacher is an Elder Bairn

She did know the story, or at least one ridiculously close.

• Jossed. Kanako was a researcher looking to publish Saya's story.

The Twins didn't really come Back From the Dead

Kinda obvious.

• Yup. They were never dead to start with.

Tokizane knows about Saya and the Elder Bairns

This is why he is so protective of her.

• He does, she told him on episode 8, then he died on episode 10.
• He knew the whole time, as did everyone else in town.

Elder Bairns and humans come from the same source

Their name means Elder Children, which may mean that they are humanity's "older sibling"

• In episode 6 one of the twins does become a monster

Saya is a Vampire which is why her eyes glow red

This is also hinted at when we see increasing amounts of shots of her blood cells.

• Nope. She's an Elder Bairn.

The dog is an Elder Bairn

He does seem to watch over Saya in at least one of her battles, and causes a reaction in her.

Saya's mother was an Elder Bairn

She fought the Elder Bairn and her daughter is definitely not normal.

• Jossed. She never existed to begin with.

Saya has amnesia

Pretty simple, we see her trying to catch a light in her mind, that later looks like a sword and is accompanied by flashbacks to someone fighting Elder Bairns.

• Confirmed. Her memory was being suppressed by whatever Fumito was putting in her coffee.

Saya's mother didn't fight Elder Bairns

It was just Saya before she lost her memories.

• Episode 6 suggests that her memories weren't lost, so much as removed or hidden by her father. He managed to put her to sleep with a simple hand gesture.
• Confirmed, sort of. Saya's memories were suppressed by Fumito, not Tadayoshi, and she has been fighting Elder Bairns for a long time.

Saya's dad is manipulating her to a evil purpose.

He does love her, but he believes it is for the greater good.

• He was a helpless pawn to Fumito, just like Saya.

Fumito-san behind the whole plot.

Or... he's on the bad guys's side.

• Confirmed as of Episode 12.

Saya isn't actually her father's daughter.

She is being raised as a weapon, she was found similarly to Blood Plus!Saya, she's her dad's Replacement Goldfish for his wife.

• Semi-confirmed. She's not Tadayoshi's child, but he never had a wife to begin with, and she wasn't raised by him.

Yuka is Saya's sister queen.

A scene in the OP makes her seem to know more than she lets on.

• Yeah, episode 9 pretty much put that one to rest. And put Yuka to rest with it.
  • Episodes 11 and 12 bring the possibility back, especially when Yuka said that she looks young enough for her age to act as a high school girl when she's old enough to be involved in politics.

Yuka's on the bad guys's side.

Like the above WMG.

• As said above, she's dead. She wasn't on the bad guys side.
  • Episode 11 reveals she wasn't really dead, and WAS working with the bad guys.

Saya's teacher is researching her.

A lá Dr. Julia from Blood Plus, she said that, in that school, she had a chance to research something she wouldn't be able to see anywhere else, all this while talking to Saya.

• Confirmed by Kanako herself.

Tokizane has another form - the dog.

That's why he is also constantly fatigued and late to class.

• That would be impossible, since in episode 4, they would be in the same scene, it can also be Fumito or the Teacher though...
  • Actually, they're not. If you look closely the dog disappears right before Saya falls from the tree, followed by Tokizane cushioning her fall at the bottom of the tree. A stretch because of location, yes, but doesn't rule him out...
• Jossed. Tokizane said Bye-Bye in episode 10.
  • With him being offed for real in episode 12, and the dog appearing again, he definitely wasn't the dog.

If the singing starts again, run!

No, not for the obvious reasons. Saya is eventually going to lose control. It's pretty much guaranteed. And, when that happens, she will become a happy cheerful schoolgirl... who likes to kill people. And she WILL sing her happy song.

• Unlikely, considering how different Saya becomes when her memory returns at the end.

Saya will be forced to kill all her friends.

They will all slowly become monsters, until she has to kill them.

• Jossed, considering only one ultimately survives, and they were never her friends in the first place.

The dog is actually

• A part of Saya's subconscious trying to warn her.
• A fox.
• Saya's mother.
• The Dimension Witch.
  • Or, more likely, Watanuki.
• A Witch; take your pick of which.

The Nene scene was a Madoka Magica Shoutout.

Nene's death scene was a Shout-Out to Mami Tomoe from Madoka Magica, they were both killed in the Wham! Episode for shock value, both died the same way and the name MOTOE is an anagram of TOMOE. 

The show is a direct continuation of Blood: The Last Vampire

As Saya's visions become more and more clear, we see images of a train car getting splattered with blood, along with flashes of what is clearly a chiropteran. I posit that these are flashbacks from the opening scene of Blood: The Last Vampire.

• Extremely likely considering the final episodes and that scene at what seems to be the base.

The Elder Bairns feed on fear.

Why is it that Itsuki survived the attack on the school? Because, unlike everyone else, he fought back.

• He didn't die because he wasn't an extra.

The Guimave Saya eats had blood in it

Fumito mentions that its color is based on whats in it, and Saya seems to like them an awful lot....

• The coffee is rather suspect too. I don't think Saya's father drinks different coffee from hers because it's decaf. I think his is deblood.
  • Confirmed by Fumito.

Saya's father is a vampire/ elder bairn.

The cuts on Fumito's arm is from being fed on

• The Elder bairn also seem to be on a First-Name Basis with him and haven't tried attacking him when he's alone so far. The one in ep 10 completely ignored him standing 3 feet away but immediately went after Tokizane.
  • Confirmed. He was a half-human half-Elder Bairn hybrid.

Blood-C is a prequel to Claymore

• Fumito's experiments with Saya's blood do not end with this story. Ultimately, more half-human-half-monsters will be created with the large collection that he's hidden away and the most successful ones will become the first Claymores.