Dumped As A Trash, Then I Start Mega Evolution

I woke up as a little fire dragon, summoned by a pretty girl. Thought I'd found love? Ha. She ripped me apart, fed my dragon core to a bear, and tossed me in a trash heap. Just when I was about to die, another pretty girl found me. She contracted me, and I swallowed a toad—boom, evolution.Then the beast tide hit. Everyone ran. I chased. I devoured every monster in sight. Now my enemies stare at my divine dragon form, shaking. "Is this really that useless F-rank lizard we dumped?" Yeah, you dumped me. But watch me mega evolve into your worst nightmare.