On the back of the soaring wyvern cutting across the skies, Cassandra, nestled in Ray's arms, suddenly lurched as if struck by a powerful shock.

"Cassandra, are you okay?" Ray asked, alarmed, quickly steadying her before she nearly fell off the saddle.

"Th-thank you. It seems the penalty has just taken effect," Cassandra replied with a weak smile.

Mages are beings capable of manifesting miracles, but their power always adheres to the laws of equivalent exchange. For Cassandra, using future technology meant she had little to offer in return. As a result, the laws of causality imposed a heavy toll …