Like TV shows of any kind anywhere in the world, anime isn’t always long-running and can sometimes go off the air after a single season or a handful of episodes, sometimes leaving behind an incomplete story. Sometimes, that’s on purpose, with the goal to drive eager fans to continue following the story in the manga instead.

RELATED: Attack On Titan: 10 Anime To Watch After The Final Season

Other times, a lack of interest from viewers or a shortage of money can cut productions short. And every once in a while, the cliffhangers are a creative choice, and the endings are left ambiguous on purpose. But whatever the reason, there are several anime that leave off with unexpected, and unexplained, endings that have fans reeling.

10 Fullmetal Alchemist

Edward Elric from the 2003 Fullmetal Alchemist.

The original Fullmetal Alchemist series is well-known for its wild divergence from the source material of its manga. The story it tells loses some of the close plotting and careful world-building of the manga (and of the subsequent reboot of the anime, Fullmetal Alchemist Brotherhood) but also explores the world in a sometimes fascinating way.

The series ends on a cliffhanger, with Edward sacrificing himself and going through a portal to another world entirely. To finish the story, one has to watch the follow-up film, Conqueror of Shamballa.

9 Elfen Lied

Lucy from Elfen Lied

The Elfen Lied anime in general left many fans of the manga feeling upset and dissatisfied. For a long-running manga, the anime series had an incredibly short run of only 13 episodes.

This wasn’t enough time to really delve into the plot of the series, or to tell a full story arc. The series didn’t just end on a cliffhanger but actually left the entire second half of the story untold, much to the chagrin of viewers.

8 NANA

Nana Osaki sitting on a train in Nana.

NANA is one of the best loved and bestselling josei manga of all time. Its anime adaptation closely follows the tone and plot of the manga series in the course of its 47-episode run. NANA, unfortunately, has a very unusual problem: its manga isn’t finished.

RELATED: The 5 Most Popular Couples In Josei Anime (& 5 That Got Overlooked)

Creator Ai Yazawa put the manga on hiatus in 2009 due to health issues, and the series has yet to return, leaving the anime to end on a cliffhanger which flashes forward to a future time with no explanation for the new circumstances.

7 Cowboy Bebop

Spike Spiegel in his last moments (Cowboy Bebop)

Cowboy Bebop has one of the most iconic ending scenes in anime. The beloved series, following a group of down on their luck bounty hunters, also follows main character Spike Spiegel as he works his way toward a confrontation with a former friend and associate, Vicious.

The two have an epic showdown in the last episode, and afterwards, Spike collapses. It is never made clear in the series whether or not he died at this moment, leaving the ending ambiguous.

6 Hinamatsuri

an alien girl and a yakuza make for an interesting duo in Hinamatsuri

Hinamatsuri is a comedy series about a young girl with telekinesis who suddenly appears in the home of a yakuza lieutenant, who wants nothing to do with her but who takes care of her due to her threats of violence using her telepathy.

RELATED: A Certain Scientific Railgun: 10 Weak Esper Abilities That Are Actually More Powerful Than You Think

While the series is almost completely made up of gags and lengthy comedy sequences, a new character is introduced in the last few episodes, seemingly out to find Hina but who doesn’t actually succeed in doing so before the series ends.

5 Rosario + Vampire

Moka Ayakashi smiles while with her cat in Rosario + Vampire.

Rosario + Vampire’s ending could be viewed as a complete ending, but it’s definitely abrupt and has left a lot of fans scratching their heads. While the heroes do manage to get one over on the villain, it’s not clear if they actually won the day and, if so, how.

They then return to the Yokai Academy, where they are all students, and cheerfully go on with their day, with no real conclusion about the relationships between the characters (the romance of which is the major focus of the series).

4 No Game No Life

Stephanie, No Game No Life

No Game No Life, like Fullmetal Alchemist, ends on an unexpected cliffhanger but has a follow-up in the film No Game No Life: Zero, but the film came out more than three years after the end of the anime, leaving many fans dismayed by the ending.

The isekai series, which follows a pair of characters trying to survive in a world in which they have to gamble to not be killed, ends on the pair starting yet another gambling game, implying that they haven’t escaped this fate yet.

3 Claymore

claire from claymore

The Claymore series finale left a lot of fans extremely upset. It diverges from the ending of the story arc in the manga, and the series never continues to tell the story that follows this arc.

While the final battle alone is poorly regarded among fans as a dissatisfying conclusion to the series, the episode also features a lot of foreshadowing of events to come, which never happen as the series doesn’t continue after this episode.

2 Deadman Wonderland

Shiro And Ganta Fighting For Their Lives In Deadman Wonderland

Deadman Wonderland is another anime that doesn’t adapt the entirety of the manga series that it’s based on. The series takes place in a sadistic prison in which the characters are forced to fight and participate in Gladiatorial type tournaments, all while also trying to escape, Spartacus-style.

But by the ending of the anime, it actually isn’t very clear whether or not they succeed at doing that or if they’re still stuck inside, having spent 12 episodes doing their best to escape.

1 Spice And Wolf

holo and kraft lawrence from spice and wolf

Spice and Wolf is a fantasy romance series, so it seems likely that the main characters are going to end up together at the end. However, that’s not the case with Spice and Wolf.

A merchant named Lawrence and a wolf-deity named Holo travel together, with the goal to get Holo to her homeland and for Lawrence to be able to make the money to buy his own shop. The series ends with Lawrence spending his money to save Holo and a declaration of love that goes fulfilled.

NEXT: 10 Anime To Watch If You Liked Spice & Wolf