Junwaidan: Ichido Neta Dake no Onna ni Naritakunakatta

Stories of other people's real-life sexual experiences that you aren't suppose to sympathize with. The popular site that received over 20,000 submissions, over 10-million views, and sold 120,000 books has now been adapted into a manga in an "emotionally sensitive" way by Tomo Tagawa!
(Source: Kodansha, translated)