Seishokuki

Nogawa Izumi is a good student, and a class representative, but she has an increasingly high libido. It’s gotten to the point that she’ll claim to feel bad during class, so she can run to the nurse’s office and masturbate. When she learns that the Earth is being invaded by aliens that look like people dressed up as animals, it turns out her high sex drive may be able to help protect the Earth. The first time Izumi is attacked by the aliens, she is rescued by Usayama, a bunny alien whose race was their previous victim.