Undyne stood very still inside of a closet. The door let in very little light through the shutters. The water heater directly behind her was warm to the touch. In her right hand, she held her spear. In her left hand, she desperately clutched the doorframe. A shadow passes the door. She crouches as low as possible and tries to get out of the light. All of a sudden, a cascade of thumps eminated from the room adjacent to the closet. A figure stomps past at high speed, sending shivers down her spine.
Undyne crouches lower and lower until she appears as a ball of fish with a spear. She shivers like an earthquake and stares down the hallway. She sees a shadowy figure pick up several books from a shelf, rather large ones with hundreds of pages, and lob them at what seems like nothing.
"DID YOU GET IT!?" Undyne screams through the door to the closet. "I.. UH..." Alphys shouts back from the kitchen. "I THINK SO!"
Undyne uncurls and peeks through the door. She sees a book on the floor shake. Alphys jumps onto a chair and shouts as a rat emerges from the pile of books.
"SHITSHITSHITSHIT!!!" she screams. She stands too far back on the chair, leans against the backboard, and shouts again as the entire thing tumbles onto its side. She stands up and runs down the hallway towards the closet in which Undyne is hiding. "HELP!!! HELP!!!" she screams. "I CAN'T!!" Undyne responds, clutching her spear in her arm. She then looks at the spear, then looks at Alphys. "WAIT, uhh... Fine." she says, opening the door a crack and passing her spear through. "PROMISE ME that you'll be careful with it." she says. "Alright, OK, sure thing!" Alphys responds, clutching the pointed stick, slowly walking down the hall. Immediately, she turns around and opens the closet door. "TAKE IT BACK! I CAN'T DO THIS!!" she screams before crouching beside Undyne in the closet.
"Wait, waitwait... heheh... it's uhh, it's just a rat, right?" Undyne says. "Yeah, I... I guess we shouldn't really be that scared of it, right?" Alphys responds. "I... Yeah, right?"
"Right. Yeah."
They both emerge from the dark closet and Undyne grabs her spear back. The two begin slowly stepping forwards, Alphys in back this time. "So, what... what will we do when... we catch it?" Alphys asks. "We'll... uhh... kill it, right?" Undyne asks in return. "Yeah."
"So, what if... what if it's, like, cute?" Alphys asks. "It isn't. It never will be. It can't be. It wants to KILL me, Alphys!" Undyne whisper-shouts. Just then, the rat in question turns the corner and begins sprinting towards the two. Alphys jumps out of the way and hangs off of the closet door with her fingers in the shudders. Undyne dodges to the right and lodges her spear into a wall, screeching out in fear.
The rat stands up in front of the closet door and hangs off of the lowest bar. "HELP!!! HELP!!!" Alphys screams infernally at the rodent. The rat chirps and then lies down on its side. "IT'S.. It's..." Alphys sputters.
"God. Fucking." Undyne says. "Dammit." Alphys finishes, hopping down from the door. "Well, does it carry... diseases, or whatever?" Alphys asks.
"God, I hope not." Undyne responds, picking up the rat, which rolls onto its back and begins sleeping. "Jesus. This thing shouldn't be this cute." she says. "I thought you said-" Alphys says, before Undyne rolls the rat onto her right hand and sticks her left index finger towards the ceiling. "Don't. Start." she says.
Undyne hands the rat to Alphys, who squeals in fear upon seeing the rodent and backs off. "Dude, it's sleeping. It doesn't even... why is... Why is it sleeping?" Undyne asks. "It's... tired. From all the... trying to kill us. It's just going to kill us LATER!" Alphys says, slowly backing into the closet door.
"I... seriously doubt that." Undyne replies. "I think it's friendly."
"LOOK AT IT! IT'S A KILLING MACHINE!" Alphys says, adamantly pointing at the rather unassuming rat. "Alphys, I thought I was the one who was scared of rats." Undyne says. "Well, if you're not going to hold the rat, can you go find a box?" she says. "...This is going to be humane, right?" Alphys responds. "Hun, I want to keep it. Look at it!" Undyne responds. "It's very charming."
"IT'S A RAT!" Alphys responds.
"IT'S A FRIEND!!" Undyne retorts.
"If you say so, I- I guess..." Alphys says, climbing the ladder into the spider-riddled attic. She swears she can smell brownies. She sees a box of printer paper, grabs it, and dumps it out on the floor. She brings it downstairs and pokes holes in the lid.
"There. Here's your rat-box." Alphys says, hesitating.
"I like it." Undyne responds, quickly grabbing the box and laying the rat gently inside. "Hey. You don't happen to have any, like, bedding you're willing to part with?"
"No. Never. Not at all. No." Alphys responds.