Gleipnir

グレイプニル

6.9(252,794)

MAL Score

Ranked #5155

Popularity #469

Action
Ecchi
Mystery
Super Power

Episodes: 13
Duration: 23 min per ep
Aired: Apr 5, 2020 to Jun 28, 2020
Status: Finished Airing

Synopsis

Shuuichi Kagaya seems like a typical high schooler—until the moments when he inexplicably transforms into a monster. With no clear idea how he gained these powers, he keeps them hidden, hoping no one ever finds out. One night, he spots a building on fire and rescues a girl trapped inside, but in the chaos he leaves behind his phone.

The girl, Claire Aoki, soon tracks him down and corners him about what she saw. When Shuuichi insists she’s mistaken, Claire forces the issue by pushing him from the school roof, leaving him no choice but to transform to survive. She captures proof and uses it to pressure him for information about other monsters—answers he can barely provide. Claire reveals her own motive: she’s searching for her sister, who has also become a monster, and she needs Shuuichi’s help to find her—while others pursue the same mysteries for their own reasons.

Otaku Consensus

Gleipnir is a divisive seinen thriller whose best assets are PINE JAM’s sharp action animation, Kazuhiro Yoneda’s willingness to make the body-horror imagery uncomfortable, and the volatile Clair-Shuuichi dynamic that gives the battles a kinkier, more psychological edge than standard super-power tournaments. Its reputation is held back by pacing: many viewers felt the 13 episodes spend too long withholding the core mystery, then end on an unfinished cliffhanger just as the larger plot finally accelerates. The result is not a cleanly satisfying adaptation, but it has enough visual bite and nasty interpersonal tension to explain why a vocal minority defends it as underrated.

Why You Should Watch

Watch Gleipnir if you want a battle-royale mystery that feels sweaty, invasive, and morally compromised rather than sleek or heroic. It scratches a similar itch to Darwin’s Game or Mirai Nikki, but with more emphasis on body horror, sexual power imbalance, and the question of who gets to control a “power” once two people are required to use it effectively. PINE JAM gives the fights a tactile weirdness: the mascot-like monster design is not treated as cute for long, and the series keeps pushing the discomfort of zippers, flesh, guns, and proximity. It is best for viewers who can tolerate ecchi provocation and an incomplete anime ending in exchange for a grimy supernatural puzzle with unusually intimate combat mechanics.

Key Characters

C
Clair Aoki(VA: Nao Touyama)
Clair is the character fans tend to remember first: a manipulative, fearlessly confrontational heroine whose dominance turns the series’ partnership dynamic into psychological warfare as much as action.
S
Shuuichi Kagaya(VA: Natsuki Hanae)
Shuuichi stands out less as a conventional action lead than as a reluctant vessel, making his passivity part of the show’s central tension rather than a simple weakness.

What Makes It Stand Out

1
PINE JAM animated the 13-episode series, and the production is most often praised for its action cuts and grotesque transformation imagery even by viewers who criticize the writing. The show’s visual identity depends on making a soft mascot silhouette feel physically wrong.
2
The anime is structured around withheld information rather than straightforward tournament escalation, with Shinichi Inozume credited for series composition. That choice is also the source of its biggest complaint: reviewers repeatedly singled out the middle stretch for giving only small pieces of the central mystery.
3
Takahiro Kishida handled character design, while Kanna Hirayama and Kyouko Yufu are both credited on prop design. That division matters in a series where costumes, zippers, phones, weapons, and other physical objects are not just accessories but part of the power-system language.
4
AniList’s tag profile captures how unusually abrasive the genre mix is: Shapeshifting at 87%, Death Game at 79%, Gore at 73%, Femdom at 73%, Body Horror at 69%, and Nudity at 64%. The series does not separate its fanservice from its horror; it often fuses them, which is exactly why reactions are polarized.
5
The final stretch has a reputation for picking up momentum without delivering full closure. Multiple viewer responses note that the last episodes become more plot-forward, but the TV anime stops before the source’s broader answers can land.

Fun Facts & Trivia

Fun fact 1: Gleipnir is based on the manga by Sun Takeda, who is credited as the original creator. Web discussion of the completed manga is notably warmer than many reactions to the anime, with at least one reader calling the source an underappreciated gem despite slower sections.
Fun fact 2: The anime aired as a spring 2020 TV series from April 5 to June 28, 2020, finishing at 13 episodes. Its MAL popularity rank of #469 shows it reached a large audience even though its score, 6.94 from over 252,000 votes, reflects a split reception.
Fun fact 3: Kazuhiro Yoneda directed the adaptation, with Yuka Okamoto credited both as art director and for art design. Those credits help explain the show’s emphasis on atmosphere: ordinary school and rural settings are staged against a much more lurid supernatural underside.
Fun fact 4: The two leads have high-profile Japanese voice actors: Nao Touyama plays Clair Aoki, while Natsuki Hanae plays Shuuichi Kagaya. Their performances are central to selling a relationship built less on trust than pressure, fear, and forced cooperation.
Fun fact 5: On AniList, Gleipnir holds a 66/100 score and 2,513 favourites, closely mirroring its MAL reputation as a popular but contentious series. It is the kind of anime with more committed defenders than its aggregate score suggests.