On my desk was my half consumed can of Coke.
When I returned from lunch I had a half consumed bottle of Pepsi with me.
I mixed the two so I would only have one container on my desk.
I have been violently ill ever since.
As we all know Coke and Pepsi are fierce competitors. It would seem that this fighting nature has transmitted itself to the actual product and the two rival beverages are now fighting a war in your stomach.