*spoilers*
Wait so the way to becoming a Jenni was sharing your power with someone that didn't have any? Wouldn't that mean that Ginny became a Jenni by sharing herself with Deuce twice? Or is sharing your life force different than sharing your element or something?
*still spoilers*
Ginny is a Djinni, something entirely different from a Janni. Djinni is an elemental being of Air, Efreeti is an elemental being of Fire, Marid is an elemental being of Water, and Janni is an elemental being with all the elements, but with a very weak form of each. Janni were formerly other types of elemental beings and gave their powers to someone else to become a Janni. Janni can live independent from Lucerna, but the others need Lucerna to live. There's also an Earth elemental (rounding out the 4 elements), but I don't remember if a name for them is given, and I don't remember if anyone in the game is or was one of those. In terms of the strength of their powers, Marid > Efreeti > Djinni, with Janni basically not having any elemental powers. Not sure where the Earth ones would fit in there.
Ginny bisected her life twice to save Deuce's life two times, but that process has nothing to do with the process of becoming a Janni.
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