Jubeichan form she would be comfortable with.
Jiyu had a magical origin even before she got the Lovely Eyepatch, via her mother.We find out that Jiyu inherited her magically hot fever from her mother; a fever so hot that it boils icepacks. Her father wasn't even surprised at this. He also knew how to cure these fevers, via Intimate Healing. Her mother died from a similar fever, implying it has nothing to do with the Lovely Eyepatch. Traditional origin of a Magical Girl. This is the real reason Jiyu was a candidate for it, not her "Juicy Bon-Bons". Her "magical girlness" mixed with the Eyepatch's power, which resulted in her being a kind of hybrid Magical Girl Ninja.
Many of the cast are Half Human HybridsMostly ghosts and spirits.
Koinosuke was seduced by a Tree Spirit, who used magic to temporarily overcome his GeasHence Ayunosuke being born.
Bantarou is Ash's fatherTake a good look at Batarou. Take a good look at Ash. I caught on to this resemblance the first time I watched an episode of Jubei.