Chad surveyed the smooth curved edges of the sink, and decided the drain was his only option for escape. He slipped a couple times due to the spilled potions. He didn't know what they might do to him, but so far he felt okay. He pried the stopper loose. It was heavier and more awkward to shift than he expected. Of course, being 5 inches tall was the problem.
Chad looked down the dark hole, it was probably only about a foot to the trap, but at his current size that would be a 20 foot drop. Maybe he could shimmy down the drainpipe? Chad braced his arms on either side of the drain opening. He lowered his feet and legs into the hole. He tried to brace himself with his legs against the pipe walls, but either the walls were too slick or maybe the potions coating him were too slick. He felt a weakness in his belly, like he was going to empty his bowels. But that didn't happen. Instead his feet dropped and his torso and legs stretched. His feet splashed into the cold water at the bottom of the trap. Chad blinked. His shoulders braced him on the sink drain, but his feet were now 20 feet below him, relatively speaking. Maybe he could climb out of the sink now.
Chad straightened his arms to lift himself out of the drain, but suddenly, his arms were like rubber. He shot down the pipe racing toward his feet. The momentum propelled his feet through the trap and along the pipe leading to the sewer line.
Chad shrieked. It was a lot like riding down a dark tubular slide at a water park. Except for the wretched smell and disgusting slime coating the inside of the pipe. His slick rubbery body flowed like liquid down the drains. He was like a living plumber's snake. He was taking a lot of the slime within. Splash. At last he reached the six inch main line and began trudging forward in the dark. In the distance, Chad heard a toilet flush. He panicked and started to run. He heard the roaring water rushing down the pipe toward him. He hoped it might dissipate before it reached him. He really hoped it was only pee.
Splash, a wall of water impacted him, and he was swimming or trying too. His limbs were too rubbery to swim. The current carried him forward.