fucks yeah

saying yeah in a more excited way or when u agree with what someone says "that lady was a bitch" "fucks yeah she was"

Derek" do u wanna go to see MGK in October?"
Steph" FUCKS YEAH I do!!"

Steph" that dude was a straight sketchball"
Derek "fucks yeah he was"

or another form would be "fucks no"

"I aint hangin out with them, fucks no"

or
"fucks no, I aint getting up early