Fukumene is literally pronounced, fuck-you-mean. It is a corruption of the phrase: "what the fuck do you mean." Fukumene is used when in a state of confusion and/or hysteria.
John: Dude we have a math test today!
Andre: Fukumene, a math test? I didn't study at all!
Lacy: I was just calling to let you know I just got on the parkway heading home.
Sister: There's a big accident on the parkway, it's been back up all day, I forgot to tell you.
Lacy: Fukumene, you forgot?!