Saint of the Sanctuary

Tenno transmigrated after his fateful meeting with Tractor-san, the uncle of the trusted Truck-kun that catapults people into different dimensions and makes them reincarnate.
And where did Tenno land? In the magical world Everni. And currently, Everni is in turmoil: The vampire kingdom of Cure is abducting children. No one knows why, but there are records of this happening approximately every 10 thousand years.
Unfortunately for Tenno, he transmigrated into the body of a slave boy, just 8 years old, that was supposed to be sold to the royal family of Cure. The original died before that could happen.
Now, not remembering anything about his family, he wants to gather more information about this wondrous and dangerous place.
The data gathering system inside his inter spatial ring assists him in this, and after he meets the enigmatic vampire princess, he gets wrapped up in many mysteries surrounding the family of Cure.