Why do Japanese people like to grow a Ren Dan beard?

Because the Japanese emperor at that time had such a beard, and the Japanese at that time worshipped or were superstitious about the emperor. Seeing that their "emperors" all had such beards, they all scrambled to get the wind to have such a "Ren Dan beard", which was all the rage in Japan at that time. By the way, South Korea, at that time, Korean soldiers liked to grow beards, which were called "beards" in China and "moustaches" in Japan. During the Nanjing Massacre, Koreans were recruited into the Japanese Huncheng Brigade in Nanjing, and Korean soldiers indirectly participated in the killing of China people! Now, an old man in Nanjing mentioned the Nanjing Massacre that year, and he felt that "bearded" soldiers were more cruel than "moustached"!