Grave Of The Vampire 1972 (aka...Seed Of Terror

Grave of the Vampire is a 1972 American vampire film directed by John Hayes, and starring William Smith, Michael Pataki, and Lyn Peters. Its plot follows a vampire who rapes a living woman, resulting in the birth of a child who feeds only on blood. It is based on the novel The Still Life by David Chase.
The film is also known as Seed of Terror (American reissue title).
In 1940 California, college student Paul proposes to his girlfriend, Leslie Hollander, in the cemetery where they shared their first kiss. During the proposal, Caleb Croft—a serial rapist and murderer in life, now a vampire—awakens from his crypt. Caleb brutally murders Paul and rapes Leslie. A local lieutenant, Panzer, investigates the crime, and discovers that Croft's tomb is also empty.
Panzer visits a catatonic Leslie in the hospital. When he shows her a mugshot of Croft, she violently recoils. It turns out that Croft was a prolific murderer and rapist in Massachusetts, who was electrocuted to death in the Boston Subway while attempting to flee from police. To prevent locals from vandalizing his grave, his body was entombed in California. While wandering through the town, Croft enters the home of a local housewife, kills her and feeds on her blood. Before Leslie is discharged from the hospital, her doctor informs her she is pregnant, but that the fetus appears abnormal. Leslie believes the child to be Paul's, but her doctor insists she get an abortion, which she adamantly refuses. Meanwhile, Panzer returns to Croft's tomb, but is killed by the vampire in the process.
Some months later, Leslie—orphaned by her parents—gives birth to her son. Her housekeeper, Olga, urges Leslie to contact the town doctor, as the infant is pallid and will not take milk. Eventually, Leslie soon finds that the newborn gains strength by consuming blood. Leslie begins drawing her own blood into syringes and filling bottles to feed the baby, whom she names James.
Thirty years later, Leslie dies. Blaming him for his mother's suffering, the adult James chooses to dedicate his life to hunting his father. In one of the towns along his journey, James enrolls in a folk mythology class, where he meets Anita Jacoby, a graduate student, and her roommate Anne Arthur. James is unaware that the professor, Adrian Lockwood, is in fact Caleb Croft, who has assumed a new identity. During their first seminar, James gains Croft's attention by espousing his knowledge of the story of Charles Croydon, a 17th-century Englishman thought to be a vampire, as well as the case of Caleb Croft. After class, Anne has a brief conversation with Croft, during which he tells her she reminds him of his late wife, Sarah.
Later that night, Croft murders the university librarian. Meanwhile, James attends a party with Anita, who informs him she believes Croydon and Croft may have been the same person. James subsequently has Anne over to his apartment, and the two have sex. Meanwhile, Croft visits Anne and Anita's apartment, finding Anita etc