Torture Princess: Fremd Torturchen, Vol. 2 (light novel‪)‬

My name is Hina! I am my beloved master Kaito's eternal lover, his faithful companion, his soldier, his weapon, his love outlet, his sex doll-and his bride!
Hoping to play a larger role in the battles ahead, Kaito begins to dabble in magic-and not a moment too soon! Shortly after Elisabeth, Kaito, and Hina accept an invitation to a bloody banquet and vanquish their host, the Governor, Elisabeth falls victim to a trap laid by the Grand King and has her powers sealed away! With the Torture Princess in her newly weakened state, the Grand King, Fiore, seizes the golden opportunity and leads a dark crusade against Elisabeth's castle, hoping to finish her off once and for all. Only two humble servants remain to stand against the army of one thousand: an immortal groom and his blood-drenched bride...