Master of the Ghost Castle

Master of the Ghost Castle summary:

Mila, a spoiled young lady, has ended up marrying into a ghost castle where terrifying rumors are swirling. To the public, she is thought to have died for lse majest, and there is no way to escape...! It is Mila's "role" to leave behind an heir for the ghostly castle master, Lord Rihart, but...!?The marriage comedy of the most terrifying couple begins!