Paying for your pet’s medicine and surgery bill isn’t the only thing to worry about in Shift at Midnight now that Guillermo has gone missing. Here’s what you need to know about Shift at Midnight‘s missing dog poster.
Shift at Midnight lost dog poster: Can you find Guillermo?

Guillermo is a brown Labrador with a yellow collar who goes missing during night 10, where a missing poster with his information appears on the notice board during that shift. The notice board acts as one of the primary ways to get new information in Shift at Midnight (that, and listening to the Store Manager’s instructions when he calls or leaves you a note).
But unlike the side quests in Story Mode, which you must immediately act upon when given, the missing dog is treated differently. Though there’s a $50 reward that seems relevant to gathering bonuses through completing the Store Manager’s requests, there seemingly appears to be no way to locate Guillermo. It’s as if this is simply a red herring and that there is no in-game model of Guillermo to find.
After all, Guillermo is not the service dog, Tofu, that you have to serve when he comes into the store (as Shift at Midnight tries to trick you into shooting this innocent pup). Instead, he is a random dog that has gone missing and likely relates to The Dentist, or perhaps another customer who has been replaced with a doppelganger, making Guillermo ownerless.
Your immediate response likely sends you to the surrounding forest to check for a stray dog wandering around. But viewing the missing poster does not open a relevant dialogue option to investigate customers that night. Therefore, the inclusion of this poster is likely here for lore purposes and to fuel our drive to protect our own pet, being the entire reason we’re risking our lives working the shift at midnight.
The community on Shift at Midnight’s Discord Server has searched for Guillermo and had no luck finding him. They seem to confirm to newcomers that there is no missing dog to find. The clearest evidence that Guillermo cannot be found in-game is found on the actual poster. There’s no option to call the owner’s number in-game, and that’s because there is no lost dog to find.