本作是以性转换(TSF)为题材的成人游戏。
此后系列化,至今已发售6部作品(包含复刻版、重制版等则为13部作品)。此外,直到《Xchange3》为止都是以本作主人公相原塔库雅(相原たくや)为主人公的系列,而《Yin-Yang! X Change Alternative》之后虽然冠以系列名称,但世界观已是另一个故事。
The protagonist of the game is a young boy who is about to graduate high school and is looking for a job to support himself during the upcoming college years. However, fate intervened and arranged a bike accident, which resulted in a meeting with a creature from another world - a cute fox-girl named Sharan. She needs nothing else but to be together with the hero; but a mysterious voice tells him: "one wish has been fulfilled, two more to go"...