Demon Beast Invasion(1990)

Demon Beast Invasion is a science fiction series set 100 million years after an ecological disaster banished Demon Beasts from Earth. Now they've returned with a sinister plan: breed with human females to create hybrid creatures that will pave the way for a full-scale invasion. When 19-year-old Kayo is assaulted by a possessed lover, she becomes pregnant with a terrifying mutant offspring. Interplanetary Mutual Observation Agent Muneto must intervene to protect Kayo and stop the creature from fulfilling its destructive purpose. The series blends horror and science fiction as humanity faces an existential threat from within.