"Currently, hundred of different alien species come and go, living their lives on the Earth. Species that come in peace, aggressive warlike species... Aliens with all kinds of personalities live among us, maintaining a precarious balance."
Contrary to the belief of its native inhabitants, Mankind isn't the only sentient species living on Earth. Actually, individuals of about five hundred alien species call Earth home for reasons as diverse as their biological peculiarities. The Diskun and Erald, for example, come to Earth because Humans Are Special to them; others are refugees, like the cursed inhabitants of the dead planet Conwell; some come looking for love, like the future Mucbak Queen; and not everyone has a choice on the matter, like one of the last mermaids of Horn. Their existance is a secret to the average human citizen; however, with so many aliens around, it's inevitable some humans eventually get tangled in their bizarre stories. These humans are said to have entered the Level E.Level E is one of the least known works of Yoshihiro Togashi, of YuYu Hakusho and Hunter × Hunter fame. Prone to Art Shift, Genre Shift and Mood Whiplash, it can go from a wacky parody of Pretty Freeloader shows to a tragic Horror story without missing a beat, and it lacks a definite protagonist, having an Ensemble Cast whose most recurring character is a certain Prince from the planet Dogra.An 13-episodes Anime adaptation by Studio Pierrot aired in 2011.
Humans Are Special: For the Diskunians and Eralds, humans are off limits. Who knows which human might be a potential baseball star or parent to one? The Mucbaks think humans have great genetic potential.
Inferred Holocaust: Subverted. After Yukitaka accidentally blows up the Prince's ship, a clip show plays of the funerals of those caught in the blast. Double subverted when it turns out that there were no casualties, much to Yukitaka's relief.
Kid Hero: Both lampshaded and subverted in one of the stories. The kids who the Prince dragged into one of his crazy anti-boredom schemes completely called him out on actually picking kids to fight monsters. They eventually go along with it kicking and screaming, sometimes literally.
"Clive from the planet Jacqueline Ess" is a reference to the Books of Blood. Come to think of it, the whole series might have been inspired by that famous horror anthology, given the episodic structure, some of the themes explored, the black humour and occasional forays into the weird and macabre.
Twist Ending: What do you know, humans aren't the only sentient beings native to Earth. Good news for a certain Woobie mermaid.
Regarding the Conwell story: Apparently, the entire arc was just Prince Baka pitching a story to an executive which gets rejected for being too dark. Even though the Prince suggests that the Conwell aliens exist, it's hard to know if he's telling the truth knowing his usual habits.
The Stinger: After the end credits of the final episode, it is revealed that the cat was a spy all along.
Throw It In: Vic Mignogna was told by the director to use whatever voice he wanted with Prince Baka. No word on what they told Daisuke Namikawa.
The Unmasqued World: At the end of the anime, Baka was outwitted and married the princess of Magra, removing under observation status from Earth — and revealing the entire alien armada to the entire planet.