Retardao

It's when something is so mind-numbing, your face uncontrollably spasms into some sort of an ahegao, not out of arousal, but your brain malfunctioning. As if your brain is getting licked.

A similar thing can occur with extreme ASMR tingles, like Japanese ear-licking ASMRs.

*insert feather into your ears*
"Gwah-uah!! God dammit! Quit it!"
"Ahahaha! Your face pulled a retardao."