Lactic acid
The burning senstation you get in your legs and buttocks after a really hardcore sexual episode.
after two hours of cunnilingus his/her tounge was filled with lactic acid.
While fucking her doggy style his ass and legs began to feel the effects of lactic acid and he could no longer stand
While fucking her doggy style his ass and legs began to feel the effects of lactic acid and he could no longer stand
My cheeks are full of lactic acid
The act of laughing so hard that your cheek muscles' anaerobic respiration goes into overdrive and overflows with lactic acid as a result.
hahaha, alan you're so funny my cheeks are full of lactic acid.