Bangkok Triangle
When 2 buddies and 2 girls from Thailand engage in a sexual act where one girl jerks off one buddy while playing with the second buddy's balls. The second girl jerks off the second buddy while playing with the first buddy's balls. Also know as a Two-Handed-Nancy.
Dude last night my buddy and I had these two girls up in our hotel suite, things got crazy and we ended up getting a Bangkok Triangle.