The 100 stories is like a form of ritual and it has a physical form like a piece of paper that can be burnt. Anyone who touches it who's not the one who started the ritual will get those bruises and ended up dying. Yuuma's abusive step mom is dead & his father. After Hina tried to burn the paper, the ghost probably was strong enough to completely posses someone's body which is Hina's. The horse plushie is probably the same ghost possessing it. The ghost can be his biological mom but we never know, seems evil to me.
LASTLY, I'M SO MAD KIDO DIED WTH HE DIDN'T DESERVE THAT
The 100 stories is like a form of ritual and it has a physical form like a piece of paper that can be burnt. Anyone who touches it who's not the one who started the ritual will get those bruises and ended up dying. Yuuma's abusive step mom is dead & his father. After Hina tried to burn the paper, the ghost probably was strong enough to completely posses someone's body which is Hina's. The horse plushie is probably the same ghost possessing it. The ghost can be his biological mom but we never know, seems evil to me.
LASTLY, I'M SO MAD KIDO DIED WTH HE DIDN'T DESERVE THAT