The Familiar of Zero S02 E02 The Vow of Wind and Water

The supposedly dead Wales appears and takes Henrietta to Albion. He uses his vow from their earlier days to convince her into following him. Saito and Louise goes to rescue Henrietta. Wales, later revealed to be revived and controlled by Cromwell's ring, is defeated by Louise with a dispel spell. Wales is released from the control of the ring and asks Henrietta to make a new vow with him before dying again.