Few things are more frustrating than getting to the end of a particularly gripping series, only to realize the finale you so hotly anticipated is utter garbage. Whether a promising anime jumps the shark midway through, or a fantastic series wraps with a WTF anime ending that even the most perceptive viewers couldn't see coming, bad conclusions can make you want to tear your hair out. Good anime with bad endings can leave you feeling burned long after the final credits roll, and in the worst case scenario, an awful anime ending can ruin a whole series.
Following the son of Satan's journey to become an exorcist, Blue Exorcist features memorable characters, an engaging plot, and awesome animation. The series has a lot going for it, but the ending totally undermines its efforts.
As the finale draws near, Satan — the show's antagonist — seems practically invincible, and his plan is about to come to fruition. Before that can happen, though, he's foiled through deus ex machina power-ups the heroes did not earn. Although the villain has never shown any compassion for his children (let alone the human women he impregnated), he suddenly expresses remorse in the show's final moments.
This invalidates everything viewers know about him, and comes off as a contrivance staged for cheap drama.
The 2003 version of Fullmetal Alchemist definitely had its moments, but its ending left much to be desired. After Alphonse sacrifices himself to revive his older brother using the Philosopher's Stone, Ed decides to make a sacrifice of his own. In order to definitively destroy the Gate of Truth, Ed goes through it with a group of soldiers who need to return to their world.
While his plan seems to succeed, he'll have to stay in whatever new world he enters, separated from his brother and everyone else he cares about. To make things weirder, he emerges in the real world, circa World War II.
For a while, the second Digimon Adventure series seems like it's going to end on a high note, but the epilogue is a total trainwreck. The final moments reveal everything about the DigiDestineds' futures, including who they marry, what their kids are like, and what they do for a living. Unfortunately, most of it plays like poorly-written fanfiction.
Every single character has at least one child. The kids are basically clones of their parents, down to the wild hairstyles, which is just plain creepy. With regards to the marriages, most of the characters marry outside of the DigiDestined, and viewers learn almost nothing about their mystery spouses. A lot of viewers were excited to see the relationship between TK and Kari pan out, so the creators' decision to ship them with random newcomers feels like a missed opportunity.
Then comes the jobs. Nearly all the women work stereotypically feminine jobs; they're fashion designers, kindergarten teachers, and housewives. To make matters worse, some of the men have totally unbelievable professions. Sorry, but Matt does not have what it takes to be an astronaut, though Davis's decision to run a noodle cart seems oddly fitting.
A mysterious alien cube suddenly appears on Earth, inciting the events of KADO: The Right Answer. It starts off awesome, exploring how alien technology impacts geopolitical politics in a nuanced and plausibly realistic manner. However, things begin to go downhill after the first nine episodes, and by the end of the once-unique series, it's little more than a montage of boring battles.
The final episodes retain none of the detail and precision that make the beginning so special.