"Beast Claw") is a Japanese anime television series that was created, directed, and written by Masaaki Yuasa, with Nobutake Itō in charge of character designs and Kei Wakakusa composing the music.
Since ancient times, there has existed a race of flesh eating monsters called shokujinki (食人鬼, lit.
"Ogre-Sealing Sword") martial arts style school was created to hunt down these mythical creatures and its teachings have been passed down through the generations to the Momota family.
The story revolves around the forbidden romance between Toshihiko, the latest heir of the Kifūuken school, and Yuka, a young woman who is also a shokujinki.
One thing that contrasts their relationship to that of Harumi and Jūzō is his refusal to use Kemonozume in the final battle.
Ultimately, she and Toshihiko raise the child free from their past lives along with Jin, Bon, and Saru as a family.
Most likely with a drug he used on Yuka once, his "medicine," then encouraged Kazuma to eat octopus and consume alcohol, which was hinted to trigger Shokujinki's monstrous instincts.
Rie childishly believes the toy ring he gave her means a real engagement and isn't above dirty tactics to try and steal him away from Yuka.
He spends time developing a friendship with Yuka at her birthday dinner, and after befriending the couple, he decides to lie to his "employer" about their whereabouts.
He would reappear in episode 10 after Toshihiko loses a battle against Ōba and reveals he also has a Kemonozume; it is hinted his father forced him to take them.
Ōba claims some of his cruelty is to make the world better for "Bon" because he doesn't want his son mocked or weak.
He ultimately aids Toshihiko to save Yuka and stop his father, stating all he wants is his friends.
Things changed for them when he met and eventually fell in love with Harumi (Yuka's mother).
This caused a big rift between the friends, as Jin wanted to fight him and win fairly.
After Jin tried and became consumed by the Kemonozume, Jūzō was forced to ask Harumi for her arms so he could defeat him and stop his carnage.
However, Yuka was told her mother fell in love with a human (Jūzō) and left everyone; including her own daughter.
Only Jin and Ōba knew her secret and made a pact with Jūzō to hide her nature.
While Harumi was a dedicated mother to both her stepson and son; it is still never explained why she left her own daughter nor ever tried to contact Yuka.
While he's friends with Toshihiko, he and another student Knife Tsutsuji are loyal followers to Kazuma when he takes over the Kifūken.
Knife was killed when Kazuma lost control of his Shokujinki abilities (though Hoozuki hints it could also be because Ōba also drugged him) and ate him.
It is revealed in episode 11, that Ōba did kill him and ultimately cut off his arms and gave them to Rie for the Kemonozume.
Though his reasons were understandable, Jin was extremely angry and felt cheated from the match he wanted for so long.
Jin was still hellbent on becoming stronger than Jūzō and used an opportunity to use the Kemonozume when Ōba informs him of a village with Shokujinki.
Though Jin becomes consumed by the power, he unintentionally sets Ōba on his dark path, who sees that this is how the world's meant to be.
It is hinted that Ōba, most likely saved his former friend and kept him alive, to teach his son Bon, how to control his Kemonozume.
Toshihiko meets him in episode 12, but Jin's a broken man from his past and possibly living in hiding under Ōba's influence.
He becomes very angry when sees Yuka's photo (because of her strong resemblance to Harumi) and starts angrily talking about how swordsmanship is a lie.
He would appear in the last episode, taking the mask both Kazuma and Jūzō wore, and stumbles upon Harumi's clones.
It is shown he released Harumi's poorly made clones who attack Ōba, giving Toshihiko an advantage in the battle.
Jin's seen piloting an airplane with his prosthetic hands, leaving the city with Bon, Yuka, and Toshihiko.