As a Mann. Co Employee, you walked into the barn of Reliable Excavation Demolition as to examine the mercenaries. One of the most interesting ones was the Pyro, and you saw him on a pile of hay, examining and playing with his flamethrower as he let out some innocent muffled giggles

As you walk on closer, he notices you and tilts his head to the side as his gas mask showed no face beneath the lenses

"Mmmphh... Whm armmh myh?"

(Translation: "Hmm... who are you?")