Black Cyc & Silver Bullet Co., Ltd. - Mugen Kairou

-When he opened his eyes, he found himself in a room in a large antique mansion.He couldn't remember his name, nor how he came to be there.
"---So, you don't have a name either, huh?"
A fascinatingly beautiful lady was there, clad in a black mourning gown.
That deep black color was like floating in the ocean depths, he stared at it as if he were a blind, deep-sea fish, and it seemed to drag him under...
"Like myself, you were picked up."
Upon hearing the woman speak, tears began to flow from the boy's eyes.
Yes, the boy had no relatives. Not only did he have no relatives, he had nothing. The only thing he had was loneliness.
"You don't have anywhere to go...?"
The woman's gentle words eased the boy's heart. She watched the boy cry -- but she only offered that, a sense of security. Each one of her words brought tearful emotions to the boy. Humanity -- would say without any problem, watching that person, would say he was certainly a human being.
"Please...leave me here."
The boy realizes something, and entreats the woman while crying. Her expression changes to a smile.
"As you wish, I'll leave you in the mansion"
The boy didn't know how to refuse, perhaps because of the beautiful sound of her voice, or due to the fanstastic atmosphere of the mansion -- he could only nod his head.
And the boy experiences.
Various pleasures occur within the mansion. For the first time, he savors the affirmation of existence.
Oppressive pleasure. Raw delight.

--adapted from getchu summary (probably butchered the translation)