The kimono is a form of geisha zashiki, which is a part of traditional Japanese sexual culture, along with hanabi (flower train) and nyosai (female body building).

Originally, it was a game between geishas and sasshikis at festivals like Shogetsu in the Fireworks Alley. The woman is naked (or only the lower half of her body is exposed), and starting from a seated position, she bends her upper body toward her back and pours sake into the concave area formed by her thighs and lower abdomen, using the woman's own body as a vessel for the sake.

Because sake leaks down through the gap between the thighs of a slender woman, it is more appropriate for women who have a fuller figure in kimono. The name comes from the fact that "pubic hair swaying in the sake looks like kimono". Wakame sake has a long history, and although there are rumors that Ito Hirobumi enjoyed it during the Meiji period, it has generally been more common since the mid-1950s.

Introduction to Wakame Sake

The character "菜" (菜) is both a form of the Chinese character and an ideogram. The character was first used in the Small Seal Script of the Shuowen (Figure 1), where the upper part of the character "菜" resembles the shape of two grasses, and the lower part of the character "采" is similar to the character "采". In the Han Dynasty script, the upper part of the character "菜" looks like two mountains, and the lower part is "木". In the Regular Script, the character "菜" is almost identical to the modern script, except that the upper part of the character "艹" has changed from the center to two segments. After the regular script, there was no great change until it developed into modern Chinese.

The chemical composition of wine is ethanol, which generally contains traces of heterohydric alcohols and esters, and the concentration of edible baijiu is generally below 60 degrees (i.e., 60%) (a few have more than 60 degrees), and baijiu is purified by fractional distillation to more than 75% for medical alcohol, and purified to more than 99.5% for anhydrous ethanol. Wine is brewed from grain by fermentation. Drinking alcohol in any amount is not beneficial.

The above was taken from the reference: wakame wine