The Cynewards and the Serpent Trials.

After their aunt’s death, siblings Jessica and Andrew Cyneward move into their family estate, only to discover that their heritage involves much more than they ever imagined. Thrust into a world brimming with supernatural forces, the teenagers must balance high school life with the daunting task of battling demons and other paranormal and mystical creatures. Alongside them, the Seven Deadly Sins—unexpected houseguests bound by a curse which imprisons them on the estate—serve as their allies, mandated to serve the Cynewards as earthly wardens.
As Jessica and Andrew navigate this extraordinary reality, they must determine whether these events mark the beginning of an exciting new chapter—or if a more sinister force is gathering in the shadows.