Spellbound Horrors

This is a series when many kids with many differences, but have one thing in common.
They all come in contact with a special force that preys on those under 18 for their pure blood. His name is Takuna. Takuna is a mix between the well known devil and an adult man with razor sharp teeth and dagger like claws.
There are 3 ways to conjure Takuna: read from a special spell book, willingly sacrifice a blood related family member under a blue moon, or be sacrificed under a full moon. There is always at least one person dead after conjuring Takuna and no one sees it coming.