Cang Qing's life was only for her master - King Cang, no, he should be the emperor. Not only because he saved her many times and was humiliated for her... But also because of the almost gentle warmth, so even though he knew it had a purpose, he still fell into it a little bit, willing to cut through the thorns and be the master with a sharp blade. Even if the ending is to be abandoned, it will be satisfying.
It's just... When she has decided that she only lives for her king, and loses this person, where should she go as a blade that only aims to overcome thorns and thorns...