I can't even remember the characters' name. The story was set in historical Japan (not ancient, but definitely wasn't modern day). A little girl who appeared to have foreign blood mixed in her was bought by a wealthy adult man. I think it was later revealed that the clothes the girl wore were passed down to a doll that looked just like her. The author also has another manga in which a (probably teenage) girl was taken care of by an adult man after her parents passed away.

This author's particular works were, in my opinion, borderline pedophiliac as it features sexual abuse and likely to be very disturbing for most people. I'm just looking for it because I feel a bit irritated for not being able to remember.

Sounds like this one? Kindan Or from the same author. Read one chapter and I couldn't stomach it and happen to love my trashy smut/hentai.

I'm in idol hell T.T

That's the author's another story and what I was looking for. Thanks a lot!