"There's something fishy about all this..."
"Oh that's just Undyne!" -- Gallifreya
[AN: I think MobTale fits this prompt the best]
"He said he'd be here," said Papyrus.
"Your pal says lots of things," rumbled Sans. "You sure he's on the up and up?"
Papyrus smiled. "Of course he is. He's responsible for the training that got Undyne to notice me. I trust him with my life."
"Do you trust him with the kid's life?" said Undyne. She was wearing her battle armour and surveying the street corner with her remaining eye.
Frisk, held under her elbow like a sack of flour, squirmed and peeved.
"I don't think they like being held like that," said Sans.
"What do you know? Humans can withstand all kinds of hardships."
"Frisk likes hugs."
"I'm not a hugger," growled Undyne. Nevertheless, she thrust the human child at Papyrus. "You are."
Frisk clung to Papyrus like a limpet.
"He's late," announced Sans. "If he shows, kid, you tap my shoulder if it's the bad guy."
Frisk nodded, and began to yawn.
"I'll wake you if he shows up," whispered Papyrus. "Nighty night, little human."
Hours past in damp, dark silence. The only action that happened was an alley cat going about its business, tail held high.
"...something smells fishy about all of this," muttered Sans.
"Oh, that's just Undyne," cheered Papyrus.