The fallout that ensues after a righteous infliction of retribution characterized by a horrible cunt. This is distinguished by an aftermath by the ill-intention on the part of whoever is causing the wrathtermath. The United States sees the disinhabitablization of Hiroshima and Nagasaki (too soon?) as an unfortunate aftermath of trying to end a war quickly, where Japan sees the broken and impoverished Chinese a justified wrathtermath of mindlessly slaughtering their impure neighbors.
Bro: How come you're only eating chili and beans and chili-beans and raw garlic?
Me: Because I hate you.
Bro: But you're only hurting yourself.
Me: Wait for the wrathtermath.