Collar Stained With Blood

Former revolutionary assassin Sylvie was abused by a general. She escaped, was taken in by a priest, but the priest was killed. She rescued young Benny, trained him for a decade. They evolved from master and slave to soulmates, hunting down the general. Benny died protecting her. Sylvie killed the enemies, carried his body to the sea, and slit her own throat to join him.