The Last Water Magus In The Apocalypse

Humans should have gone extinct hundreds of years ago. The prolonged earthquake. The volcano that doesn't stop spewing lava. The huge tornado that blows away skyscrapers. The ocean that submerged many continents. When humans began to surrender to all these disasters, hope arose. Hope that came from 4 people who look the same as other humans but have something that other humans don't have. The Magus Master of Earth who can stop the earth from shaking. The Magus Master of Fire who can return lava to the bowels of the earth. The Magus Master of Wind who can calm the furious tornado. The Magus Master of Water who can subdue the ocean. The Elemental Legend of The Apocalypse. That's the name they get after successfully becoming human hope in the apocalypse. Now the surviving humans reside in a new continent that was never on the map. The Three Districts Continent, that continent was all they had. Hundreds of years have passed. The Master Magus of Water is cursed to have only one successor to the Water Magus per generation. Unlike the other three magus, a new Water Magus will not appear if the previous Water Magus is already dying. Now humans are faced with the second apocalypse. A parasitic infection that turns humans into zombies, and El-Demons—The Demons with elemental powers that can match the elemental magus. The Three District is on the verge of collapse because of the zombie and El-Demon apocalypse. The only hope that humans have is in the hands of a young man who is lazy and doesn't want to interfere with things. Earth, Fire, and Wind Magus can match any other elemental El-Demon, except fire. The fire El-Demon will be the biggest challenge for the three of them if Calvin Herodust doesn't develop his huge potential. Calvin is just a teenager who manages to live a normal life without anyone knowing that he is a water mage from birth except his father and his two siblings. For him, his simple life without showing his water magic that troublesome him was more than enough. “You will become the greatest Water Magus who will protect the world. Join us!" "No. I don’t want to.” "Come on. We need you. What do you want? House? Gold? Game console? We'll give them all!" "I've got them all." "Beer? Beautiful and sexy woman?” "I'm only 16. And my sister said—" "Kitten?" “Maine coon kittens. Deals?” "I don’t know what that is, but we have baby lion.” “That’s better! Deals!" Thanks to the baby lion, so The Last Water Magus is finally moved to protect the humans in The Apocalypse. Will Calvin succeed get the title of The Master Magus of Water and protect the world? Why was only his brother proud and happy to see him become a hero?