Hey guys I really need help finding this yaoi manga where the uke is a young boy who is treated like a sex doll.

Some sex company bought his body and experimented on him and turned him into some kind of sex toy. He has an amputated arm which is replaced by a horse hoove (if I'm not mistaken) and he does not have any memory of his past life. He also has deer/horse ears attached to his head. He can't speak and has little to no emotions, but whenever he's with the seme, he is happy.

The seme works for the company I think, or his friend worked there, I'm not sure. But he basically needs to "use" the uke and then tick off of a list to see if there's anything that could be improved or altered, for example the quality of the oral sex or sth. However, the seme always refused to touch the uke in a sexual way, and didn't like doing the job. I think he tried to teaxh the uke how to speak/read at some point? It's pretty wholesome.

Extra stuff I remember: there was a chapter where the uke was dreaming. And in that dream, he could speak and write etc, and could talk with the seme.
The cover art was black and white, and shows the young boy standing facing front while naked.

Sabi no yume 🙂