The world of anime is miniscule compared to the expansive manga universe. While there are some amazing manga adaptations, due to the sheer volume of manga, there are many that are left unexplored onscreen.
Sometimes, it's understandable that a fantastic series has gone under the radar – Keiko Tobe's With The Light features excellent storytelling, art, and character development, but follows a mother trying to raise an autistic child in a society that doesn't always understand her family's needs. Not only is it focused on a niche topic, it also lacks a conclusion thanks to the author's untimely death. However, there are some wildly popular complete series, like Vagabond by Takehiko Inoue, that seem like they should have been made into an anime ages ago.
Sometimes manga adaptations don't work as anime, but these manga feel ripe for the jump from the page to the screen. Every season, new manga adaptations appear on the anime scene, so it's entirely possible the shows on this list – and other amazing manga out there lacking an anime version – will get a second life in anime form someday.
Take Future Diary, make it an isekai, and add a protagonist who is actually competent, and you get Toshiaki Iwashiro's Psyren. Ageha Yoshina, a high school student, helps anyone with anything for money, so when he receives a mysterious phone call asking if he wants to go to a place called Psyren – which may be connected to his missing classmate Sakurako – he accepts the offer. There, he must compete using newly awakened psychic powers if he ever wants to return home. This exciting story could easily be adapted into an equally enjoyable anime.
In HERO's Horimiya, Kyoko Hori and Izumi Miyamura are two high school students whose classmates don't see them as they truly are. Though Kyouko looks like she has everything under control, she's actually under a lot of pressure at home, as she's responsible for watching her younger brother and taking care of the house. Meanwhile, Izumi appears to be a gruff, brooding nerd, but he actually is just quiet and bad at studying – oh, and he has a tattoo.
The manga is about how the two get to know the real Kyoko and Izumi, and they slowly grow close. It would be amazing to see such a nuanced love story adapted into an anime.
Takehiko Inoue's Vagabond is a prize-winning manga that's sold millions of copies worldwide, so the fact it hasn't been adapted since its conclusion in 2015 is baffling. It's a fictionalized version of the life of Musashi Miyamoto, a famous swordsman from the 1500s. With beautiful art and nuanced characterization, this manga transports its readers to another world. With 37 volumes, it might be difficult to animate the whole thing, but an arc or two is well overdue.
There aren't any standout examples of anime that deal with a realistic zombie outbreak. Sure, Highschool of the Dead and School-Live! are scary, but they don't make viewers consider how they would survive an undead apocalypse. Kengo Hanazawa's I Am A Hero is different. It takes a man already struggling to hold his life together and pits him against a horde of zombies – which he stands little chance of defeating.
The outbreak plays out in a realistic manner: people cling to the comforts of society and make the outbreak worse by staying close, and then rioting ensues. The zombies are terrifying because they still look human, just with bottomless pits where their eyes should be. An anime adaptation could revolutionize the zombie genre.