Based on the erotic game by Noesis. 
 
Yui Kurahashi quarreled with her parents and ran away from home. As Yui walks around town, Yui meets a friend and Yui has been fooled into joining a dating site called Free Friends. Yui's just waiting for someone to contact her even though Yui does not know much about it. The main characters accidentally find it and its contacts. That night, they met in a city full of libido and.... 
 
(Source: Translated and Edited from Nekopoi)

Based on the erotic game by Noesis. 
 
An internet bulletin board called "Free Friends" is used as a dating site, where young girls' bodies are sold cheaply. Shuuji, a teacher, registers on the site to kill time. One day, a student from the school where he teaches, Yui, appears before him. Yui uses the bulletin board without knowing the meaning of posting on it, and Shuuji becomes abnormally excited by her, so he forcefully takes her virginity...? [From Part 1, Kurahashi Yui] 
 
(Source: Parabook, translated)

Based on the erotic game by Noesis. 
 
Advanced series from Furifure The Animation. 
 
In this second series, the story is more intensive, where the woman named Sumire (or her nickname is Sumi) became a prostitute in order to get money for her daily life. The regular customer is a teacher. Unwittingly the teacher turned out to be Sumi's brother. Then what will happen to both of them? 
 
(Source: Translated and Edited from Nekopoi)

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