Shawn is based on the Animated Lust (rated PG!) forum participant known as Shawn and, as such, is copyright to himself, and used with permission.
Psychedelic-man is an original character (or at least concept) and is copyright to me.
The below shows and characters are used for fanfiction purposes only, I disclaim all ownership:
Digimon and associated characters and concepts are © Akiyoshi Hongo - Toei Animation; © Bandai
SpongeBob and associated characters and concepts including SpongeBob SquarePants, Patrick Star, and Sandy Cheeks are © Viacom International Inc.
The Beatles: Yellow Submarine and associated characters and concepts, in this case the Yellow Submarine itself, are © Hearst Corp. (King Features Syndicate Div.) and Subafilms Ltd. The Yellow Submarine sequence is loosely inspired by the original movie and Peter Max scenes therein. (The Yellow Submarine really exists; I believe it is in Monaco.)
Undersea
A hole opened up into the real world and Shawn and Mimi hurtled toward it. On the far side stood what looked like a yellow kitchen sponge wearing brown pants and a tie. Mimi and Shawn exchanged a look of disbelief.
"What on earth is that?" the sponge exclaimed, pointing toward the hole and them inside it.
A pink starfish appeared. "Ooooooo – pretty..." it said.
A squirrel, improbably wearing an upside-down goldfish bowl on its head, took one look and stated quite definitely, in a Texas accent heavy enough to drive spikes through bricks, "Whatever it is, it ain't natural!"
"Aiiee-ya!" shouted the squirrel and slammed a karate kick at the enlarging hole of numbers.
Which promptly collapsed, leaving Shawn and Mimi inside.
So they didn't fall through into that reality, but went somewhere else instead.
They seemed to have been doomed to come out underwater – the hole reopened and spit them out through something that looked extremely like a laundry chute onto the floor of a submarine. It was yellow, and it appeared to be abandoned, but it was definitely going somewhere...
Shawn looked out of a porthole. A marching band in turquoise and shocking pink uniforms was parading along the sea floor behind a drum majorette dressed in mirrors. It was from the reflections on her outfit that Shawn discovered the submarine was yellow.
Going the other way was a neon fish – a real neon fish whose sides flashed ads for restaurants and upcoming events.
Suddenly streaking past the sub in a classic Superman pose was a vision in lime green tights and a fuchsia and electric blue cape. Sparkling stars trailed in his wake as he aimed directly for a huge jeweled cork rammed into a cliffside rising from the sea floor. He hit it full tilt, causing the cork to give way and pop through, and the ocean began to drain into the hole that was left behind.
The submarine drifted slowly but inexorably toward the hole, which had the usual ones and zeros, but instead of the common black and white, these were in rainbow colors and a variety of constantly shifting shapes, and they pulsed to their own hidden rhythm. And Shawn and Mimi once again fell though to a different reality in the wake of Psychedelic-man.