In an alleyway in between houses...
To elaborate on the situation: i was in my teens, and with tons of bullying going on, i skipped a lot of school.
I didn't have any friends to hang / hide out with, meaning i would hide in alleyways around town, or in parks, or cycle to a nearby forest.
Just waiting there, all by myself, simply for time to pass (and yes, it was as miserable as it sounds
).
Doing that though, i got a pretty good idea when some alleyways remained deserted for hours, and when some people would walk / cycle through them (mothers bringing kids to daycare early morning, other students coming home in the afternoon, etc.)
...and i still had the raging hormones a typical teenager got to deal with... and with no chance of a boyfriend to experience sex with (remember; bullies, depression, social anxiety & agoraphobia), i always had to pleasure myself.
One day i either dug up the courage - or was too horny to resist - and decided 'fuck it, i'm gonna try it right here and now!'
My favorite way of masturbating was and still is riding a firm pillow or something similar, so i rolled up my jacket and a bundle of gymclothes i had in my bag, lowered my jeans, placed my improvised pillow of clothes on the pavement, lied down on it... and started grinding away.
The whole alleyway had a slight bend in it, so you couldn't see straight through... and as i said, i knew at what hour the place was most deserted... but darn, if any fellow kid that lived around there got out of school earlier, or anyone else happened to stroll through... what a sight they would've gotten...!