So i'll make it clear, i didn't like Blood-C at all.
i didn't even watch Blood+ yet so i'm not here because i'm a fan, i just want to summarize my feelings after watching this anime:
+the characters looks good i like the design of characters and i loved their high school costume.
+the main character Saya.
+the art was decent the studio did their best and it satisfies the eyes.
(-)ofc i didn't like the story, it was slow, so badly slow, for 10 episodes same scenario : coffee,guimove,high school,the oath,a fight aaaand repeat it really killed me same and the same forever until episode 11 and 12 the
main point revealed and i was so happy to see a changing in the story, in addition, the characters are so poor i have no interest exclude saya.
conclusion: good art and design,decent sound,nice protagonist and poor story and characters. not recommended to watch first 10 episode i give it 2/10, 2 last episodes 6.5/10 overall rate 4/10. poor anime not decent.