Kagero is amoung rare kind of Ninjas serving that she is a woman. She spent her years as her Grandfather’s pupil until he was killed by her major enemy, the Kawagami. She fought with Tsimbaro a trusted friend until he disappeered. She now is a Ninja Wanderer following where her feet take her.
A possible answer to what happens to spells when a mage dies. If the spell is strong enough, say and enchantment or other permenant effect, part of the mages spirit may become lodged in the magic. It may be a way for items to gain some kind of intelligence, but a mage who has knowledge of this fact would be very hesitant about enchanting anyone or thing. He might have other plans for his afterlife than counting the change in your bag of holding.
Preists, I think, would have this sort of thing covered.