- At the very beginning man is abducted by aliens and kept in a cage of several layers of paper (aliens thought it to be a perfect cage/shield).
- IIRC aliens were communicating using brainwaves (they were telepaths?).
- Man escapes the cage and it turned out that his fear kills aliens ("fear" brain wave?).
- So he manages to escape lab(?) and the city and so he captures spaceship and sets course back to Earth.
- It turned out that there is kind of female alien onboard and her boyfriend now pursues man's spaceship.
- Looks like our man is also able to hear "telepathic communications" and is aware about pursuer and he is ok to let alien to take back alien girlfriend.
- But (IIRC) the alien can't "hear" our man, can't understand his peaceful motives ("just escape") and so alien aims a laser gun at our man and... looks like it is the end of the story.
- A bit more: all happens in the centre of the galaxy.
- Aliens live only in that central part of the galaxy, because far from the center they become stupid or lose their mind or can't think right etc.
- Aliens had some kind of term for that "fear brainwave", it was something like "fnefnob" or so.
- Read in ~1990-1995
William Tenn's "The Flat-Eyed Monster" as per Short story where a man's tears are lethal to his alien captors.
In his despair, he plucked hopelessly at the material in which he’d been wrapped. Two small sections came away in his fingers.
There wasn’t enough light to examine them, but the feel was unmistakable. Paper. He was wrapped in an oversized sheet of something very much like paper.
It made sense, he thought, it made sense in its own weird way. Since the appendages of the flefnobes he had seen to date consisted of nothing more than slender tentacles ending in either eyes or tapered points, and since they seemed to need knoblike protuberances on the laboratory table in order to perch beside him, a cage of paper was pretty much escape-proof from their point of view. There was nothing for their tentacles to grip—and they evidently didn’t have the musculature to punch their way through.
He held up a shaking, admonishing hand. Fear was gibbering through him like the news of panic through a nation of monkeys. He watched the flefnobe make the peculiar winding trigger adjustment again. His thoughts came to a stop and every muscle in his body seemed to tense unendurably.
Suddenly, Lirld shook. He slid backward along the tabletop. The weapon dropped out of stiffened tentacles and smashed into bunches of circular wires that rolled in all directions. “Srin!” his mind whimpered. “Srin! The monster—Do—do you see what’s coming out of his eyes? He’s—he’s—”
His body cracked open and a pale, blue goo poured out. Tentacles dropped off him like so many long leaves in a brisk autumn wind. The eyes that studded his surface turned from turquoise to a dull brown. “Srin!” he begged in a tiny, faraway thought. “Help me—the flat-eyed monster is—help—help!”
And then he dissolved. Where he had been, there was nothing but a dark liquid, streaked with blue, that flowed and bubbled and dripped off the curving edge of the table.
The zigzag aperture widened and Rabd bounced into the cabin, looking like a series of long balloons in his spacesuit. He glanced at the recumbent Tekt and then turned desperately, pointing his curlicued blaster at Manship.
“Poor guy,” Manship was thinking. “Poor, dumb, narrow-minded hero type. In just a second, you’ll be nothing but goo.” He waited, full of confidence.
He was so full of confidence, in fact, that he wasn’t a bit frightened.
So nothing came out of his eyes, nothing but a certain condescending sympathy.
So Rabd blasted the ugly, obscene, horrible, flat-eyed thing down where it stood. And scooped up his bride with loving tentacles. And went back home to a hero’s reception.
I helped mine quotes for that one, and your mention of fear killing the aliens, and the guy ultimately being killed by a blaster by an alien that seemed immune, reminded me of it.