Drowsy

Drowsy, A.K.A. Experiment 360, is an illegal genetic experiment created by Jumba Jookiba. He is designed to put his victims to sleep by bleating; only water in the face can awaken them. His one true place is putting insomniacs to sleep. Drowsy is voiced by Tress MacNeille.

Lilo & Stitch: The Series
Experiment 360 was the 360th genetic experiment created by Jumba with Hämsterviel's funding. He was designed to use his sleep-inducing bleat to cause his victims to instantly enter a near-permanent sleep. 360 and the other first 624 experiments were deactivated and smuggled to Earth by Jumba during his mission to capture Experiment 626.

All of the experiment pods were released and scattered across the island of Kauai.

360's pod was one of the 12 experiment pods recovered by Lilo and Stitch in "Drowsy", along with 102 (mislabeled as 239), 204, 274 and probably 604 (as his pod was seen with Jumba in "Houdini").

Since Lilo hadn't got much sleep lately, Nani threatened to ban her from hunting experiments anymore if she was unable to fulfill her duties, let alone be alert, so Stitch attempted to get Lilo to fall asleep that night.

Eventually, Stitch activated 360 and used the latter's bleat to put Lilo to sleep. However, Stitch had no idea how to wake her up the next morning when Nani called for her. To try and solve the problem, Stitch tried to make Lilo seem awake by putting sunglasses on her, mimicking her voice, and moving her around like a puppet all over town.

Meanwhile, 360 escaped and was chased all over Kauai by Jumba and Pleakley, while 360 put everybody he encountered to sleep by bleating. Pleakley had initially caught 360 in his purse, but then opened it to put Gantu to sleep when the latter was looking for the experiment. At that point, however, 360 jumped out as Gantu fell on Pleakley. Jumba then scolded Pleakley for letting 360 escape.

Gantu was later woken up by a bunch of people on the beach, who thought he was a beached whale and dumped water on him. He then received a call from Hämsterviel, who demanded 360.

Stitch was unable to wake Lilo up all day, until Jumba revealed that the cure to 360's sleeping powers was to spray water in the victim's face. After Lilo was awakened, Stitch told her that she had to meet someone at the airport. Because she'd been asleep at the time, Lilo started to worry, but Jumba reassured her that Stitch had taken care of all her appointments.

Later, after a long chase, Gantu and Experiment 625 managed to capture 360 at the Birds of Paradise Hotel. However, when they tried to use 360 to kidnap Regis Philbin (the man from the airport) while posing as bellboys, Lilo and Stitch were there for Regis since he disembarked, and protected him in every way they could.

Lilo eventually recaptured 360, named him Drowsy, and let Regis stay at the Pelekai household. In the end, Drowsy used his sleep-inducing powers to send Regis and everyone in Lilo's ohana to sleep.

In "PJ", Lilo convinced Drowsy that Stitch was having trouble sleeping so that he would put Stitch to sleep, allowing Lilo to release PJ. Strangely, however, Stitch woke up on his own.

In "Ploot", Drowsy was one of the second team of experiments (along with Finder and Babyfier) formed to try and stop Ploot. However, Ploot was easily able to defeat them, forcing the three experiments to retreat.

In "Remmy", Drowsy was one of the experiments in Lilo's dream.

Leroy & Stitch
The first 624 experiments, including Drowsy, were rounded up by Leroy and taken to a stadium to be destroyed. However, Lilo, Stitch, Jumba, Pleakley, Reuben and Gantu arrived before the experiments could be destroyed.

It is unknown whether or not Drowsy participated in the following battle between the experiments and the Leroy clones.

The Leroys soon gained the upper hand in the battle, but were defeated when Lilo, Stitch, Reuben and several other experiments performed the song "Aloha `Oe," which caused the Leroy army to shut down due to the original Leroy's fail-safe.

Trivia

 * A recurring irony has appeared with Drowsy. Stitch originally used him to put Lilo to sleep, and in his second appearance, Lilo used him to put Stitch to sleep.
 * Stitch somehow woke up on his own while under Drowsy's effects, possibly indicating that other experiments are not affected as much.
 * Drowsy's pod color is yellow.
 * Drowsy is described by the experiment computer screen as, "Experiment 360 Primary function: Sleep inducer."
 * Oddly, when Drowsy's image is reflected off of Stitch's eyes in The Origin of Stitch, he is not yawning for some reason. It is possible that Drowsy's yawning image was taken from Leroy & Stitch.