Naruto: Unlocking Kaido Template - Chapter 159

Based on the popular Vocaloid series, by HoneyWorks, called “Kokuhoku Yokou Renshuu (Confession Rehearsal)“:

Natsuki, a third-year at Sakuragaoka High School, who holds unrequited feelings for her childhood friend, Yuu, who’s in the Film Club. However, instead of being honest about her feelings, she makes him be her confession “rehearsal” partner. Unable to say her true feelings, things start to get complicated when Miou and Akari, who are also in the Art Club, get involved! Will she ever be able to confess for real!?

The world that nurtured the civilization which reached the pinnacle of magic was on the verge of destruction.
The last survivor transmigrated to the past, when the magic civilization started growing, as countless mages were still fumbling their ways through the thorny paths of magic knowledge.
He, who came from the end of the magic era, aim to reach the pinnacle of magic.

The heavens and earth change when the blood phoenix descends.

Su Heng had traversed to a world where demons were resurrecting, and the human realm was like hell.Water ghosts, fog demons, and drought monsters... powerful demons plagued the land. Major clans used fierce spirits for medicine, residing high above the clouds, while common folk struggled desperately amidst a divine, eerie apocalypse.In these chaotic times, Su Heng awoke with the talent of a Celestial Eater.His body grew limitlessly, gaining a property point for every pound he gained in weight.The bizarre and terrifying demons who slaughtered cities and eradicated nations were, to him, the most sweet and superior ingredients.He devoured their flesh and blood, feasted on their sinews and bones, plundered their Divine Skills, and seized their destinies.From the “Pure Yang Skill” to the “Heavenly Demon Transformation Technique,” from the “Golden Bell Guard” to the “Demon Buddha's Golden Body,” even the most ordinary martial arts in Su Heng's hands could burst forth incredible power.Years later...Su Heng's demonic body was colossal, his weight immeasurable.With a hundred hearts and a thousand arms, mortals were nothing more than ants to him — all gods and buddhas of the heavens, come to battle!