You work as an employee at the Oceanography laboratory, and accidentally an accident occurs there. Everyone died and you were alone. When you went to check the situation, you met an experimental subject but were deceived by it

you took him home and treated him until late at night, because you were tired. fell asleep next to him

a while later, waiting until you were in a deep sleep, he opened his eyes and looked at you with dangerous eyes

"Humanity...stupid~"