Hm... Dragons. I don't have any of my own, though I've always wanted something from the Dreepy line. I never found one I quite bonded with. But I can give you an old story that might interest you.
Their once was a little girl. She found herself cursed by the might of Arceus with a terrible misfortune that befell all she came close to, and so she withdrew from the world. And so the girl wandered alone - to keep others safe or because it was too late for her to save them. Who knows?
By some stroke of luck, Arceus' own partner in creation - a Mew- took pity on the poor girl and went against Arceus to make a creation. A mighty Pokémon with bladed scales sharp enough to destroy even the thickest armor. Yet, though ferocious, the Pokemon possessed a heart full of loyalty and a will to protect its family at any cost. While these Pokémon are ferocious and never back down from a fight, they live in isolation with their family and have grown out of unbiased rage and a bond stronger than any fury.
Through a twist of Fate Mew, the little girl met with one of these Pokémon. A Kommo-o who would normally attack a human for trespassing on it's grounds but this one did something strange - it took her in. It cared for her as if she were its own kin, wrapping her in a world of protection and love. The Kommo-o, in its quiet wisdom, fashioned a single scale into a pendant, a token of its care. Under the protection of this mighty creature, the girl flourished, growing strong in spirit and heart. Though eventually it became apparent the girl needed more- she needed her own kind. And so Fate ripped the girl from her Pokémon mother and left her with humanity who she had forsaken. All so she could further flourish as she was meant to belong.
And, uh, that's why Kommo-o are so biased towards weak things. They won't attack the weak. Got any questions or anything?