Shui Naodai - Recommendations

Alt title: Water Brain

If you're looking for manga similar to Shui Naodai, you might like these titles.

Summer Hero

Summer Hero

A giant monster suddenly appears on Earth, but along with it comes a giant humanoid that people come to refer as Summer Hero. Summer Hero defeats the creature, but its decaying corpse infects thousands of people, dooming them to a zombie-like death. Taigi Makoto is a young boy devoted to making Summer Hero pay for the damage she has caused, but he doesn't know Summer Hero's secret, and if he learns it, everything will change. It's tokusatsu with a twist for fans of Ultraman and big kaiju battles! 

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Frame Saber

Frame Saber

The "saber" are immaterial entities that take possession of the body housing to protect our world by exterminating the "frame users" from another dimension. So that when possessed the bodies hosting lose consciousness, Kaon, our heroine, keeps hers. How would she cope with horrific monsters who threaten it now?

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Kaijuu Jieitai: Task Force for Paranormal Disaster Management

Kaijuu Jieitai: Task Force for Paranormal Disaster Management

Follow JSDF officers Yamato Yoshikazu and Sakimori Konoe as they face off against monsters of unknown origin that infest the troubled, disputed waters of the East Asian sea and have humans as a preferential prey!

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Vigness San-shiki

Vigness San-shiki

Throughout the world, it has become commonplace for giant "monsters" to attack towns and cities. In such a world, the reason that Haruto stands up and fights isn't for peace, nor for his family, or for his girlfriend, but...

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Let Me Game in Peace (Novel)

Let Me Game in Peace (Novel)

1 drop of blood equals 1-Up. Other people game overnight, I game overnight and bleed. Ever since the dimensional storms descended upon Earth, numerous dimensional zones have appeared, bringing with them all kinds of dimensional creatures— Immortals, Buddhas, Devils, Angels, Elves, etc. Yet, all these strange dimensional zones can turn into dungeon instances on my phone. Other people risk their lives adventuring, I spend all my time gaming. Monsters drop dimensional crystals that boost stats, imbue new skills, and join me as Companion Beasts. These Companion Beasts fight alongside me or alone, augmenting me with their skills and strength. Rare monsters in real life? I'll just restart the game with a drop of blood to grind it. I really need a blood transfusion.

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Digimon Universe: App Monsters

Digimon Universe: App Monsters

Everyone in the world uses smartphone apps. But inside them lurks unknown creatures called "Appli Monsters," or "Appmon." The Appmon are AI lifeforms with the ability to think and act, and exist in the boundary between the human world and digital space to allow people and the system to interface and function. But in the vast sea of the internet, the "last boss AI" Leviathan takes control of the Appmon with a virus and begins hacking every system, thus starting to control the human world from the world of the net.

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Core Scramble

Core Scramble

In a world plagued by monsters swarming through portals from other dimensions, a brave group of soldiers called Clarus Orbis battles the otherworldly threat. Unfortunately, when you're an average grunt like Chaeun, survival becomes a daily ordeal, especially under the reckless leadership of his sexually arrogant commander Gayoon. Abandoned on the battlefield by the handsome Gayoon, Chaeun desperately fights off an endless bug onslaught only to be rescued by the mysterious renegade leader Moonhoo. At first, the man playfully flirts with Chaeun, but slowly the realization dawns that Moonhoo and his Core Hunter group have insidious ambitions on the dimensional portals. And only Chaeun and his hot-tempered leader Gayoon stand in their way.

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Monster Pet Evolution (Novel)

Monster Pet Evolution (Novel)

Three years ago, the animals and plants on Earth underwent crazy and unexplainable changes that included transformations, reversions, and the addition of otherworldly species. And it was the start of a brand-new type of profession in the new generation of humanity - Monster Trainers, people who specialized in taming monsters. On his 18th birthday, the protagonist of the story, Gao Peng, suddenly received the ability of being able to see the attribute data frame of monsters. With his ability, he aspired to become the strongest monster trainer that ever lived while looking for a method to revive his parents!

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Meteod

Meteod

Thirty years ago a series of meteorites rained down on Earth, destroying much of civilization. Decades later, pockets of humanity are beginning to reemerge, but many of the children who have been born after the crisis have been mutated by radiation from the meteorites. They are called the Meteorite Breed. Tooi, a fourteen years old kid that eats a lot, is one of the Meteorite Breed. But he is a rare one...

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Nobunagun

Nobunagun

Earth is under attack from otherworldly creatures known as Evolutionary Invasion Objects, and only the agents of DOGOO, a government organization, can keep the monsters at bay. Armed with special weapons infused with the souls of distinguished historical figures, these fighters, recruited by an alien who watched its planet be destroyed by the Objects, are humanity’s best chance against the invaders. Teenager Shio Ogura used to be nothing but a loner and a military otaku, until one day she and her class went on a field trip to Taiwan and found themselves smack dab in the middle of an Object attack. To help save a new friend, the girl picks up a gun infused with the famed samurai Nobunaga Oda, thus securing her fate as the newest member of DOGOO, and protector of humanity!

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