The Labs of Dr. Alphys were unusually devoid of her frantic studies this particular night.
Not uncommon, considering Alphys' recent schedule, trying to make time to visit Undyne over by the Hotland/Waterfall border between keeping her experiments caged up in the True Lab or working on some servo failures in Mettaton's new body; the poor lizard was overworking herself, and it finally fell upon Undyne to sneak her out for a drink at Grillby's to chill out and relax.
Now, the labs were dead silent, save for the occasional rattling of the vent systems keeping the rooms at an acclimatable temperature... or the occasional rat scrambling through the vents looking for food.
Except one particular vent line, where a shadowy figure was making a mad dash for the robotics wing, scaring away anything that crossed its path.
The rumbling of the vents gave way to a loud crash as the figure dropped down, smacking its face in the floor.
"OOOOOOWWWWWW!! WHO PUT THAT HOLE THERE!? USELESS, USELESS, USELESS!