blood sucking; blood thirsty.
Etymology: from Middle English sanguyne, ”a blood-red cloth” < Old French sanguin < Latin sanguineus, ”bloody”, equivalent to sanguin-, stem of sanguis, ”blood” + sugent, derived from Latin sugere, “sucking”.
"Carmilla", by Joseph Sheridan Le Fanu:
A young woman living at her father’s castle is the narrator of this novella. When a mysterious and beautiful stranger is stranded at the castle in odd circumstances and becomes a guest, the heroine quickly forms a close bond with her —but she subsequently discovers that her “friend” has a dark and lethal secret.