Ticking clocks, dripping faucets, electric humming, anything repetitive. When I moved in with my girlfriend, she had an ancient, battered electric alarm clock that always put out a faint hum. It sounded like a wounded wildebeest when the alarm went off. She's hearing impaired, so she never noticed the hum. She liked the clock because it was loud enough to wake even a half-deaf woman. The clock finally suffered a mysterious, brutal end when *someone* stomped on it several times.
No one can prove I did that.
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Diagnosed Bipolar II in 2012, Autism spectrum disorder (moderate) & ADHD in 2015.