Blood Cures & Blood Baths
In my books, while Eve is cursed with a type of pseudo-immortality, she is not indestructible and often her body dies around early middle age.
One of the ways she often tries to keep her youthful appearance is to bathe in blood or consume flesh.
Ancient beliefs about blood are paramount to this. They are also part of the key reasons behind martydom (aside from ritualistic murder and making religious statements) and why certain things were done to the one known as Jesus.
As vampyres would sometimes say, “for blood is the life.”