Hiro is the son of two extremely talented wizards who reside in an ancient, fantastical world full of magic and magical beasts. The continent of Japan is plagued by the presence of a giant evil dragon called Zot, and no one is powerful enough to stop the dragon from doing what it pleases. The dragon goes around, destroying cities and burning entire countries to the ground, and no one is strong enough to even try and delay the attack so that people can evacuate.
Boy Merges Himself With A Powerful Dragon, Becoming Most Overpowered Swordsman
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