He never thought that... The younger brother he had raised since childhood, the little crybaby who once said he wanted to live and die with him, would now not even be called "brother".
"If... His Royal Highness the Crown Prince asks me to guard the border, I am willing to set off today and will not come back unless I am called back."
He couldn't figure out what he had done wrong.
"But my heart towards His Highness will never change."
PS: It is an imaginary world and has no basis. Any similarity is purely coincidental.
Concept: The story of the growth of two groups