nice to meet you! ^^
oh XD lemme explain it for you *ahem*
The girl with long black hair is a reincarnation of Yamabuki otome. Yamabuki is Rihan's wife. Becoz of the former gitsune's curse, she cant bear a child. This shame brought her to her death. She left rihan with a poem, a very sad one T_T then the antagonist used otome's body as a child, and add gitsune to her body. they create false memory, n the young yamabuki thought rihan is her father. becoz she reminds rihan of yamabuki, rihan accepted her. one day, gitsune took over her body, and stabbed rihan. then, yamabuki's memories were given back, and she remembered rihan was her husband. Tragic love. when yamabuki was dying, she told this whole story XD Poor rikuo cried over her death T___T
o yea, they said Wakana is rihan's treasure, the only one that could bring smile back to rihan's face after the loss of yamabuki :')
phew, that's about it XD