A war on two fronts

When you are taking a piss and need to shit

Jim: what's up with the door slamming in the bathroom
George: I had a war on two fronts

war on two fronts

When you and your boi are hittin it hard from both sides and you both cum at the same time, leading to a friendly alliance lasting for 15 years

"Oh hell yeah me and James totally gave Molly the war on two fronts, we're like best buds now"