Yuusha ni Narenakatta Ore wa Shibushibu Shuushoku wo Ketsui Shimashita. OVA

When Keyaru acquired his powers as a Hero who specialized in healing all injuries regardless of severity, it seemed that he would walk the path to a great future. But what awaited him instead was great agony; he was subjected to years of seemingly endless hellish torture and abuse. Keyaru's healing skills allowed him to secretly collect the memories and abilities of those he treated, gradually making him stronger than anyone else. But by the time he reached his full potential, it was far too late—he had already lost everything. Determined to put his life back on track, Keyaru decided to unleash a powerful healing spell that rewound the entire world back to the time before he began to suffer his horrible fate. Equipped with the anguish of his past, he vows to redo everything in order to fulfill a new purpose—to exact revenge upon those who have wronged him. [Written by MAL Rewrite]

After the mysterious mana calamity, Rudeus Greyrat and his fierce student Eris Boreas Greyrat are teleported to the Demon Continent. There, they team up with their newfound companion Ruijerd Supardia—the former leader of the Superd's Warrior group—to form "Dead End," a successful adventurer party. Making a name for themselves, the trio journeys across the continent to make their way back home to Fittoa. Following the advice he received from the faceless god Hitogami, Rudeus saves Kishirika Kishirisu, the Great Emperor of the Demon World, who rewards him by granting him a strange power. Now, as Rudeus masters the powerful ability that offers a number of new opportunities, it might prove to be more than what he bargained for when unexpected dangers threaten to hinder their travels. [Written by MAL Rewrite]

Kintarou Ooe is a specialist in part-time work, riding all over the highways and byways of Japan on his trusty steed, the Mikazuki 5, and finding employment wherever he can. His adventures bring him knowledge and experience that can't be taught in a classroom, from political corruption to the delicacy of a young woman's heart. With nothing but the open road before him—not to mention the many beautiful women along the way—Kintarou pursues his spirit of education while attempting to hold down his various odd jobs, however undignified they may be. As he learns from each task he takes on, who knows what could happen? He might even be able to save the world one day. One thing is for sure—this will all be very educational! [Written by MAL Rewrite]

It happened suddenly: The dead began to rise and Japan was thrown into total chaos. As these monsters begin terrorizing a high school, Takashi Kimuro is forced to kill his best friend when he gets bitten and joins the ranks of the walking dead. Vowing to protect Rei Miyamoto, the girlfriend of the man he just executed, they narrowly escape their death trap of a school, only to be greeted with a society that has already fallen. Soon, Takashi and Rei band together with other students on a journey to find their family members and uncover what caused this overwhelming pandemic. Joining them is Saeko Busujima, the beautiful president of the Kendo Club; Kouta Hirano, an otaku with a fetish for firearms; Saya Takagi, the daughter of an influential politician; and Shizuka Marikawa, their hot school nurse. But will the combined strength of these individuals be enough to conquer this undead apocalypse? [Written by MAL Rewrite]