Black Dragon Reborn – Contracted by the School Belle?!

Synopsis

I, the Black Dragon King, had just returned from slaying a god when my own brother betrayed me. My soul barely escaped into a dragon egg, only to be summoned and turned into a little lizard. As if that weren't enough, the woman who formed a contract with me immediately commanded me to swallow her necklace. I incinerated it with a single blast of dragon fire. From there, I rose back to power—one-shotting bosses, transforming into a half-dragon, and taking down everyone in my way.