Gakuen Monogatari '93: The Instinct

Millions of light years away from Earth, on a planet called Cicero, there existed a highly advanced civilization. However, it was all but destroyed by a life form known as "Barius", a parasitic creature that caused living beings to completely give up to their sexual instinct and innate aggressive tendencies, effectively turning them into monsters. To avoid global contamination, the inhabitants of Cicero left their planet. The remaining creatures, infected with Barius, used a capsule capable of space travel, and eventually showed up in our galaxy. The capsule containing ferocious monsters is nearing the Earth. Unaware of this unimaginable danger, the protagonist of the game, a young teacher in a girls high school, thinks of nothing but sexual pleasures...

Gakuen Monogatari '93: The Instinct is a Japanese-style adventure with constant menu-based interface. Usually the player has to complete a certain task in every specific room before being able to explore further. The verb commands typically lead to sub-menus of objects and characters that are possible to interact with. Beside the usual "Look", "Talk", and "Move", the commands also include the more rare (in Japanese adventures) "Take" and "Use", which allows possession and manipulation of inventory items.