Japan’s anti-prostitution law (Baishun-bai) criminalizes vaginal intercourse for payment. However, "Enkou" operates in a grey loophole: the agreement is for "accompanying" (dinner/drinks). Sexual acts, if they occur, are framed as spontaneous adult consent between two parties after the paid date has begun.

The numbers "45 54" likely refer to the track gauge, which is a critical aspect of railway infrastructure. In Japan, there are several track gauges used, but the most common ones are 1067 mm (3 ft 6 in) and 1435 mm (4 ft 8.5 in).

The numbers "45" and "54" could represent the pipe's outer diameter (45mm) and length (54mm or 5.4 meters), respectively. This theory is supported by the fact that Japanese manufacturers often utilize specific numerical codes to identify their products.