Ed Kemper was a large man. He spent most of his life in very small spaces.
He was, unlike many killers, more than willing to openly discuss both his crimes and his feelings about them. Unlike most, he did not pretend to innocence or argue his liability. He also spoke freely about the urges he felt, and their origins.
“When I see a pretty girl walking down the street, I think two things: one part of me wants to take her home, be real nice and treat her right; the other part wonders what her head would look like on a stick.”
He was fifteen when he killed his grandparents. He said that he had killed his grandmother “to see what it felt like”; also, he was angry at them because they had taken away his rifle. Most killers will try to justify a crime, by giving reasons they think anyone might have done it. Kemper quite openly admitted that curiosity about killing, and simple anger, were his main reasons for the killing. He then killed his grandfather, as well, most likely to prevent retribution or further punishment. It was also a way for him to leave the living situation, as he disliked living with them.
“…my grandmother who thought she had more balls than any man and was constantly emasculating me and my grandfather to prove it. I couldn’t please her. It was like being in jail. I became a walking time bomb and I finally blew. “
He was imprisoned for these killings until he was 21. During his confinement, he was diagnosed paranoid schizophrenic and tested with a fairly high IQ. He was an intelligent person- but his mind was a bit broken. Whether the diagnosis of PS was accurate or not (diagnostics at that time did not recognize sociopathy or ASPD as proper diagnoses) could be questioned. (He is currently being treated for paranoid schizophrenia.)
He went to live with his mother when he was released.
This was probably a bad idea.