Kuro Gal ni Natta kara Shinyuu to Yattemita.  

I Turned Into a Gyaru and Tried Out My Best Friend, Kuro Gal ni Natta kara Shinyuu to shitemita., 黒ギャルになったから親友とヤってみた。

Shion and Rui were known for their success in picking up women. Tonight was another night for Shion to hook up with girls, but he took a strange drug that caused him to transform into a girl. When he woke up, he realized he had turned into a girl. Meanwhile, Rui was searching for Shion but failed to recognize him due to his new appearance and started flirting with him instead.

Kuro Gal ni Natta kara Shinyuu to Yattemita. has been published digitally in English as Fucked By My Best Friend by WWWave Corporation through Coolmic.