Straight romantic non-erotic

In Xia Kingdom, the general's granddaughter, Situ Xiu, is an eerie existence. She isn't only weak and cowardly but she is also a stutterer! One day, her younger twin brother decided to run away on a whim after he was appointed young general... Meanwhile, the emperor, not knowing the situation, issued an imperial edict, sending her younger brother to the borders to defend the country from invaders! Under the circumstances, Miss Situ had no other choice than to pretend to be her younger brother