The availability of aftercare for patients returning to their native countries is a significant issue associated with medical tourism. Such problems have also arisen regarding sex reassignment surgery (SRS) in Japan. As Thailand is a well-known destination for medical tourism related to SRS, Japanese people travel to Thailand to receive high-quality, inexpensive surgeries. In recent years, there have been reports of people who have undergone SRS overseas and have been denied aftercare in Japanese clinics. This is because the details of the surgeries performed on these individuals are unknown, and aftercare is complex without knowing these details. The inability of these individuals to receive necessary medical care makes them so-called “gender refugees.” Despite these risks, one of the reasons that Japanese transgender people visit Thailand is the Japanese legal system. Under Japan’s official family registration system, individuals need an SRS to change their gender status. This study provides background information on such issues and reports on recent notable cases. Finally, comments on the future outlook are provided.