It's because killing her 'father' is the last good thing and the first bad thing she ever did. After all he was a heinous criminal in her last life as well as now. and she was only using him for her revenge against the godess from the start anyway. Which is why she decides to be evil and not a saintess. that's why she 'made the criminal her dad' and went with him instead of with the priest as she did in her last life. It was the first important decision to change her destiny. ヾ(❀╹◡╹)ノ~ And she had to kill him to become the new head of the organisation. So that she can use them for her own ambitions in the future. ٩(๑❛ᴗ❛๑)۶
Anyone have spoilers on why she killed her adopt dad?