@Deathbonewitch - The singers daughter dies by choking on the cigarette, that her mother (now a contractor) was addicted
to, and thus caused her to now chew, and throw them up, as her punishment, as well as using her powers.
But mainly she feels utter guilt, for her daughters death, and thus tries to quarrel with it, by doing the same, when
she eats, and then trows up the cigarettes to feel what her daughter did.
@nimiru - Kirsi / Yin, was a girl, it's not formally explained, but she is 100% referenced to as a doll, which she
is, and then in the end her powers magnify.
But as we saw in the first episodes with the other woman, whom was taught to be real, she was a doll with implanted
emotions of a human, and thus may be the same for Yin, whom has the same body, and emotions of Kirsi, and
memories.
But there is episode that was released on DVD;
2008-03-26
26. Beneath the Fully Bloomed Cherry Blossoms
I don't know if that would explain anything, but I haven't seen it, so can't say for sure if that would
provide some insight.