Kaori is your average Japanese schoolgirl. Early in the movie, she and her boyfriend Tetsuo were caught by clowns. They punched her and ripped her shirt off like they were going to rape her while Tetsuo was forced to watch. Shortly after, he started to go crazy. She dies within the bowels of Tetsuo's mutated body by being crushed by expanding fat cells and drowned by blood. I don't think she had it very well in the movie. In the manga, she died, but she was not killed inside of Tetsuo's body. She was murdered.