It doesn't make sense to me either. Maybe he was abducted before the adoption, and then escaped and went back…
this is what i read in discussion:
While under Hanpyeongâs (prince) cruel captivity, the boy (then named Shinmyo - fake hongrang) once tries to escape, but Hanpyeongâs men cut his ankle tendons as punishment.
After overhearing plans to bury him alive in the bamboo forest, believing he was now "useless," the boy tries to take his own life. A boy named Inhoe, a new captive, stops him, helps him escape, and sacrifices himself by taking Shinmyoâs place.
Running through the bamboo forest, Shinmyo is spotted by Song-wol, a gisaeng queen and former lover of Yeol-guk. Recognizing that he resembles the missing Hong Rang, she buys him from Hanpyeong, names him Hong Rang, and trains him to be an assassin - not out of motherly love, but for her own revenge against Yeol-guk.
It wasn't something out of the ordinary or different; however, it was good. I loved the dark vibe of it, the execution of the story, the cinematography, and the lead's acting. The ost was cherry on top.
Who is FLâs mother? His father is the head of the guild merchant. Is her mother, the ex-lover that he abandoned for the position? Also towards the end of ep 4, we see ML addressing ex-lover as mother.
Someone tell me if he is an impostor or not? I believe he is. He met real hongrong when he was young at the snowmanâs place. They become friends and maybe shared his childhood with him.
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While under Hanpyeongâs (prince) cruel captivity, the boy (then named Shinmyo - fake hongrang) once tries to escape, but Hanpyeongâs men cut his ankle tendons as punishment.
After overhearing plans to bury him alive in the bamboo forest, believing he was now "useless," the boy tries to take his own life. A boy named Inhoe, a new captive, stops him, helps him escape, and sacrifices himself by taking Shinmyoâs place.
Running through the bamboo forest, Shinmyo is spotted by Song-wol, a gisaeng queen and former lover of Yeol-guk. Recognizing that he resembles the missing Hong Rang, she buys him from Hanpyeong, names him Hong Rang, and trains him to be an assassin - not out of motherly love, but for her own revenge against Yeol-guk.
Also towards the end of ep 4, we see ML addressing ex-lover as mother.