Kuroki Eiyuu no One Turn Kill!

The boy's first lesson from his master was about treating women with kindness and restraint—forgiving lies, listening to complaints, and never striking a woman. The master was described as a hedonist with a poor personality, often chasing women and leading the boy and his sister into hardship when money ran out. They were forced to sleep outdoors and survive on what little they could find. The master's actions caused the siblings to suffer due to his lack of strength or responsibility.