Fuck-Jaw is when you have used your mouth so many times to perform oral sex that your mouth is so tired it can no longer open to even eat. Much like Lock Jaw!
When your jaw AKA mouth can no longer open because of too much sexual acvitity.
When a mouth is fucked so many times by a big cock that it can no longer stay open for further pounding.
"Dude!""Bobby pounded that bitches mouth until she got Fuck-Jaw!"
"Apparently Debbie died of Fuck-Jaw!"
"Once again I was on another date with some bitch called Susan... the ho' couldnt take my big cock, and the dumb bitch got Fuck-Jaw after 2 hours of jackhammering her mouth!" "So anyhow I just bent her over and fucked her in the ass!"
"I heard Glenn came down with Fuck-Jaw in Miss Anderson's Drama class...Hrmm I guess hetro status may no longer be guarenteed!"