Demon Beast Invasion

Demon Beast Invasion (妖獣教室) is a manga series written and illustrated by Toshio Maeda, published by Wani Magazine. The series was adapted into a six-part original video animation of the same name in 1990, followed by Demon Beast Resurrection (妖獣教室外伝) in 1995.

Plot
Earth is being invaded by a race of unclean beasts who wish to take over the planet. However, since Earth's environment is hostile to the demons they hatch a plan to impregnate as many human females as possible in order to create a race of human/demon hybrids which will rule the Earth by proxy. But the "Interplanetary Mutual Observation Agency" sends a duo of enforcers to Earth to hunt down and destroy the alien race they call the ‘demon beasts’.

Controversy
In 1999, Jesus Castillo, a clerk at Keith's Comics in Dallas, Texas, was charged with promoting obscenity for selling an issue of the Demon Beast Invasion manga to an undercover officer. He was fined US$4,000 and sentenced to one year of unsupervised probation after the original six-month prison term sentence was suspended.