Circumstances of Tosaka Rin

Doujinshi by MTSP or JIN written based on the anime Fate/Stay Night. Like most of the author's works, it is written in NTR style. Main heroine Tohsaka Rin is forced to pay a huge debt.  After calculating and thinking that even selling her family's mansion wouldn't be enough to pay off, she makes for herself the only right decision. She agrees to help of a strange man and becomes  an elite prostitute.