While Kazumi isn't entirely selfless, she does have a strong will to protect people she cares about (and is likely to help random people in distress too) She's not one to kill her enemies, but if it becomes necessary she will resort to it. She may be the head of a yakuza group but she definitely runs it as more a helpful than harmful group.

While back home she has a harem (I don't know if this would figure into sin-sensing or not hahah), her not seeing anything wrong with it has more to do with her weird upbringing (or lack thereof kindof, due to manga influence), so I doubt this would have any affect on sin-sensing?