A short term that means Welcome Back from Iraq Sex. Take out the from. When a married man or a man with a girl returns from Iraq, the couple usually has Welcome Back Sex for about two to three days. All this sex usually ends with a baby.
Sherry: Tina I haven't seen you around for about 3 days since Jim came home from Iraq.
Tina: We've been having WBIS for 5 days stright and we're having a baby!!!!!!!!!