The Protector (Shu x Oc)

Becoming royalty has its ups and downs, nothing a young child should experience, but at the time the current King didn't realise the impact it would have on his children. Targets were stained on the backs of the future heirs of the Vampire throne by other demons and creatures, even their own blood to be able to hold such power. Karlheinz, the current vampire king did the one thing that he knew, he searched for a legendary familiar to guard his family, little did he know that someone had made the familiar rampant. Villages within the Demon universe were destroyed by the legend leaving little to no trace of any living creatures, until it was stopped. The Grand Priest chained the beast causing it to halt in its wake fighting to be set free. Not being able to keep the power to hold the beast down he decided to transfer the soul of the legendary familiar with a small infant laying on the dirt path wrapped in blankets. Two bodies were surrounding the child crushed by the fallen debris leaving the infant defenceless. This was against the Preist's beliefs but he had to do what he could to save his people. From that day on the child grew up with hatred for everyone who bullied her, til a young mortal boy met her. She became his familiar, protecting him through all costs. But as all living this do, the young man had become sick and passed, and with one final wish he wanted the young girl to watch over his adopted god daughter, Yui Komori. The two had become best friends, some may even call them sisters, but when Yui gets sent to the Sakamaki's house will Karl's longtime plan finally come into action?