Killer Gutter

''Oh no! I dropped my nickel down the drain! And that's exactly how much money I needed to ride the bus. Oh well...''

The gutter that makes a plot-important object inaccessible after that objet falls into its depths. Also known as The All-Absorbing Gutter, The Street Pit of Eternal Consumption, and That One Gutter Cliché No One Likes, the Killer Gutter will be there when something of importance needs to be ripped away from the Main. It's a good example of Spacetime Hates You as the actual chances of you losing something to a real-life Killer Gutter are a lot lesser than in fiction.