Twist knife initially with blood over it (4)
I believe the answer is:
kink
'twist' is the definition.
(I know that twist can be written as kink)
'knife initially with blood over it' is the wordplay.
I cannot quite see how this works, but
'blood' could be 'kin' (both can mean one's family) and 'kin' is located in the answer.
A single letter 'k' remains which might be clued in a way I don't understand.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for kink that I've seen before include "Sharp twist in wire or hair, perhaps" , "Eccentricity" , "Mental quirk" , "The whim" , "Quirk of behaviour" .)