Story identification: Old man has hacker neighbor who mysteriously dies

Question

Does anyone know this story? It was a novelette published with another one (I don't remember what it was) in dos-a-dos format. The premise was that the narrator is an old man whose neighbor, a hacker, dies under mysterious circumstances. A younger woman who is an expert in computer security is hired by the police to investigate what happened, and she has a fling with the narrator. After a while she dies as well, and the narrator realizes that it is an evil force that comes through electric lines is responsible for the killings. The title has interesting formatting in that it ends with a square (much like a command prompt cursor: [_] )

Answer 1

It was a novelette

"Press Enter ■", a Hugo-winning novella by John Varley, which was also the answer to this question as well as being my wrong answer to another question. It was first published in Isaac Asimov's Science Fiction Magazine, May 1984, which is available at the Internet Archive.

published with another one (I don't remember what it was)

"Hawksbill Station" by Robert Silverberg.

in dos-a-dos format.

It was a Tor Double. Since I don't have that book, the excerpts below are from the (possibly shorter) version in Varley's collection Blue Champagne.

The premise was that the narrator is an old man whose neighbor, a hacker, dies under mysterious circumstances.

"This is a recording. Please do not hang up until the message has been completed. This call originates from the house of your next-door neighbor, Charles Kluge. It will repeat every ten minutes. Mister Kluge knows he has not been the best of neighbors, and apologizes in advance for the inconvenience. He requests that you go immediately to his house. The key is under the mat. Go inside and do what needs to be done. There will be a reward for your services. Thank you."

[. . . .]

I went along the short hallway, tentatively, as people do when unsure of their welcome. The drapes were drawn, as always, so it was dark in there, but in what had once been the living room ten television screens gave more than enough light for me to see Kluge. He sat in a chair in front of a table, with his face pressed into a computer keyboard and the side of his head blown away.

A younger woman who is an expert in computer security is hired by the police to investigate what happened,

Where does one start in describing Lisa Foo? Remember when newspapers used to run editorial cartoons of Hirohito and Tojo, when the Times used the word "Jap" without embarrassment? Little guys with faces wide as footballs, ears like jug handles, thick glasses, two big rabbity buck teeth, and pencil-thin moustaches.

Leaving out only the moustaches, she was a dead ringer for a cartoon Tojo. She had the glasses, and the ears, and the teeth. But her teeth had braces, like piano keys wrapped in barbed wire. And she was five-eight or five-nine and couldn't have weighed more than a hundred and ten. I'd have said a hundred, but added five pounds for each of her breasts, so improbably large on her scrawny frame that all I could read of the message on her T-shirt was "POCK LIVE."

It was only when she turned sideways that I saw the esses before and after.

and she has a fling with the narrator.

"Somebody told me your name was Victor Apfel," she said.

"Yes. Uh, the door was open . . ."

"It's hot," she said reasonably, pinching the fabric of her shirt near her neck and lifting it up and down like you do when you're sweaty. "What can I do for you?"

"Nothing, really." I came into the dimness, and stumbled on something. It was a cardboard box, the large flat kind used for delivering a jumbo pizza.

"I was just fixing dinner, and it look's like there's plenty for two, so I was wondering if you . . ." I trailed off, as I had just noticed something else. I had thought she was wearing shorts. In fact, all she had on was the shirt and a pair of pink bikini underpants. This did not seem to make her uneasy.

". . . would you like to join me for dinner?"

Her smile grew even broader.

"I'd love to," she said. She effortlessly unwound her legs and bounced to her feet, then brushed past me, trailing the smells of perspiration and sweet soap. "Be with you in a minute."

After a while she dies as well,

It is impossible to say how long she held her head in there. It was long enough to turn her eyeballs to the consistency of boiled eggs. At some point she lost voluntary muscle control and fell to the floor, pulling the microwave down with her. It shorted out, and a fire started.

The fire set off the sophisticated burglar alarm she had installed a month before. Betty Lanier saw the flames and called the fire department as Hal ran across the street and into the burning kitchen. He dragged what was left of Lisa out onto the grass. When he saw what the fire had done to her upper body, and in particular her breasts, he threw up.

and the narrator realizes that it is an evil force that comes through electric lines is responsible for the killings.

I live by candlelight, and kerosene lamp. I grow most of what I eat.

It took a long time to taper off the Tranxene and the Dilantin, but I did it, and now take the seizures as they come. I've usually got bruises to show for it.

In the middle of a vast city I have cut myself off. I am not part of the network growing faster than I can conceive. I don't even know if it's dangerous to ordinary people. It noticed me, and Kluge, and Osborne. And Lisa. It brushed against our minds like I would brush away a mosquito, never noticing I had crushed it. Only I survived.

But I wonder.

It would be very hard . . . Lisa told me how it can get in through the wiring. There's something called a carrier wave that can move over wires carrying household current. That's why the electricity had to go.

I need water for my garden. There's just not enough rain here in southern California, and I don't now how else I could get the water.

Do you think it could come through the pipes?