When a man massages a woman's labia minora slowly with his tongue. This is said to be a "turtle sandwich" because the man is "eating-out" the woman slowly (like a turtle would). The Japanese root of this phrase is there because Japanese people have a strong affiliation with turtles, especially in their diet.
Wegner (Teacher) - You're expose is late! You're getting an F this quarter!
Young Student - NO PLEASE! I'll do anything!!
Wegner (Teacher) - Even... a Japanese Turtle Sandwich?
Young Student - (gulps)... Yes! Even that!

(the process follows)
by Franco P. March 12, 2007
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