In his youth, Kiritsugu wished to be a Hero of Justice and protect the weak. He is often haunted by Shirley's question about what he wants to become, and how she believed him to have the ability to change the world. His hesitation to kill his first love when she became a Dead Apostle resulted in the death of the whole Island. Kiritsugu, realizing that his father was the cause of this and he would continue his Dead Apostle experiment, hardened his resolve and killed his father to prevent more deaths. Kiritsugu then resolved to make meaning and worth from the murder of his father. Only by hunting and assassinating all heretic magi like his father could he truly prevent such tragedies from occurring again. He lost all traces of youthful innocence after having spent his life going through countless battles while trying to obtain a utopia that could never be fulfilled. After finding out about the existence of the Grail, he sought to use it to obtain that utopia. He feels no emotion from personal victories over his targets, seeing them as nothing more than successful taunts with calculated resolutions.