The love Triangle

So my name is Theo. My sister decided it's a good idea to buy me a toy as in a werewolf/neko pet. Well come to find out my girlfriend is a whore and my toy is my mate. I refuse to love him but what happens when he worms his way into my vampire heart? What happens when my sisters best friend comes into the picture? What happens when my rival comes after me and takes my sister away from me. Follow along on the journey to find out what happens.