Newbie here -thought I’d introduce myself...at least how I started!!
When I was a young kid of about 12/13 I started enjoying wearing nylon gym shorts, didn’t know why but loved the feel of the material.
That progressed to wearing waterproof overtrousers like Peter Storm. I did this for a while, sometimes in bed or when parents were out. I was also caught but it wasn’t really discussed and I felt hugely embarrassed.
Finally one time I was home and I had a desire to put on a two piece green rainsuit from Peter Storm. Over the head cagoule and waterproof trousers with nothing else!! I likes the pressure around my groin so I piled up some pillows, straddled them and started rubbing up and down the pillows. The smell, sound and sensation was brilliant, before I knew it (and I wasn’t sure what I had done) I had my first orgasm and came inside the waterproofs.
Since then I have enjoyed rubber, Lycra and various waterproofs. A fairly heavy pair of yellow pvc covered waterproof (like fireman’s trousers used to be) got a fair use

Cheers all