So I launched an investigation. I immediately ruled out the big boss, because I'm too scared of his power to even care if he stole something from me. He could probably drive away in my car and I'd laugh it off. I won't do anything to jeopardize my job. So that left 19 people who could have taken my water. And none of them seem to be natives of Luxembourg, so I couldn't even narrow it down (Luxembourgers are notoriously sneaky).
I decided to ask my boss if they were cleaning out the fridge today or if maybe people play pranks on others occasionally. And as I walked into her office, I saw her holding my water bottle (cue louder dramatic music)! So I boldly confronted her. I said, "Hey, did you grab my water by mistake?" (And yes, it was as intense as you're imagining.) And she looked at it, realized it was Kroger brand instead of HEB brand and apologized for mixing it up. So I had to drink HEB brand water today with lunch.