Autonomous Sensory Meridian Response, or as some people like to call it "head orgasms".
It's a tingling sensation in the head and scalp, which can be triggered by sounds like whispering or brushing, and visual stimulus like painting or drawing. For me, it's usually music or very soft touches. It only happens in a profound moment (with the exception of soft touches), and it's like... tingles that bounce form my head to my feet and back up. It just feels like bliss really...
It's COMPLETELY non-sexual.
It's really cool, and if you have certain triggers like crinkling bags or whispers, there are tons of videos out there with just people whispering and stuff that can help with sleep and relax you in general.
I was curious if anyone around here had ASMR, but didn't know that it had a name. Also, I mention it a lot, so I thought I should say what it is exactly so that you all know what I'm talking about.

