I never really bother killing flies, unless they are the kind that buzz really loud and keep hitting themselves in the glass making even more noise. There are no flies where I live now anyway.
Mosquitoes are a completely different matter though. Just yesterday I had to deal with them at the hotel, and my apartment, in last year's first months, had a ventilation hole where they would get into the house every day and make my life miserable every night. I lost the squick factor from squishing them between my hand then, although the white wall and ceiling got some unsightly blood stains .(my blood
) And then came The Device.
It looks like a tennis racket, with a metallic net that is electrified at the push of a button, with a lantern included. It was faster and wider than my palms, required only contact instead of squashing between two hard surfaces, didn't mess up my walls, and I could use it without turning the lights on. It made the next weeks more bearable, until my father helped me install a thin net over the ventilation duct and get rid of that issue.
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To build may have to be the slow and laborious task of years. To destroy can be the thoughtless act of a single day. - Winston Churchill