"I can't believe you bastards have talked me into this," grumbled Remus.
"Shut it, Moony…" Sirius shoved him.
"Is it full moon?" Peter sounded anxious.
"No, it is not full moon, and besides, if Moony's furry little problem decides to make an appearance, we know what to do, right?" James pretended to run.
"Wormtail! Prongs!" Sirius hissed. "Do you not understand what shut your bloody yap means? Filch could be around the bloody corner!"
"By the way, Moony, I meant to ask you," said James. "Why do you always insist on calling us cheeky monkeys when we're trying to talk you into something?"
"Shut your mouth or I'll shut it for you," Remus growled.
Filch's office was coming into sight. It was marked by a black, musty door furnished with a medieval-looking torch and a large brass knocker. Sirius tested it with a little push. To his surprise, it opened a crack without too much trouble. Then he carefully poked his head around it. Also to his surprise, there was no one inside. The office was a one-room affair with morose decorations, torches, and a large, stiff-backed chair that was often called "Filch's Throne." Sirius signaled the all-clear and the four of them crawled in silence towards the desk.
Sirius got up onto his knees and opened the top drawer of the desk as quietly as possible. Among the various confiscated items he found some very curious Muggle artifacts: Fake red clown noses. There was also a long piece of very yellowed parchment containing a list of incredibly clever prank hexes.
"Popricumi… Rooticareum… Insanus Wardus… Arboreatum… Snottus Spewus… These are all bloody brilliant! I'd like to try that Snottus Spewus one," James commented, scanning the list. "I wonder what it does, exactly?"
"It prolly makes someone spew snot or something to that effect," Sirius said.
"Yes, and you're supposed to be the smart one, Prongs," Remus said coolly.
"Shut it, Moony," James said casually. "Get those red plushy things, Padfoot."
Sirius plucked the fake red clown noses, the list of prank hexes, and various other items ripe for the pinching. After hiding these items in his cloak, Sirius made a quick search of the rest of the drawers in the desk, pinching whatever else seemed interesting to him, and then the foursome sneaked out of the office again.