I have been to Japan six times, and stayed over two months on four of those trips.
My experience in the "floating world " ( o-misu or honourable water) was awkward and difficult until I found an agency in Tokyo called Asian Mystique, which specializes in English speaking girls and clients. The owner is helpful on the phone, they are reliable and I made appointments in three cities with them. I also saw one independent in Tokyo, Minami, who was also English speaking and gave me one of the greatest escort experiences of my life. But going into any kind of soap land, or cosplay house will get you almost nowhere. There are the laws mentioned above, the language barrier which is significant, and their fear of disease and large sized guys which all create barries. I tried red light districts in Osaka and Kyoto and got nowhere, except for one awkaward and disappointing BJ from a auntie. If you do get to see someone, check out any tattoos particularly with numbers on them, which can be Yakuza signs. Good luck, have fun, use the trains and do not try to drive.