I didn't know, going into reading this, that both the ML and MC were character from "Smiling, Proud Wanderer". But, honestly it didn't really matter. I felt like even without prior knowledge of SPW, it's easy to go along and understand everything the plot has to offer. Though there are a few errors with explanation of plot points, I'm assuming thats just because this is technically "fanfiction".
I have one critique, and it has to do with the ML (Dongfang Bubai). He is the Invincible East, yet in the first time where the MC (Yang Lianting) is threatened, he has the ability to do nothing. It was reiterated that he was the strongest, the best in the world, yet he was bested by someone (with no reputation) in an instant. I understand that it was to move the plot along, but it completely disregarded previous aspects of the ML's character.
Besides that, I truly loved this novel. It was all about romance, redemption and realization. "Not knowing what you have until you lose it" is one of my favorite tropes and it was done so well here. The MC realized his mistakes from his first lifetime after losing his most precious person. When he comes back, ready to do anything and everything for the ML, it's so wholesome and fluffy. Despite having a few revenge scenes, this is more of a feel-good novel that illustrates a completely dedicated love.
(I'm ignoring in this that there is a slightly toxic image of castrated males or males who don't have certain features considered "manly". I don't personally agree with that, especially as that turned the ML into a more "feminine" character, as defined in the novel. It wasn't brought up too much and isn't necessarily a big part of the plot. I just didn't find it correct that the ML's castration and excess yin energy lead to him wanting to wear dresses and makeup. That's a completely normal desire, with no relation to gender, genitals or identity.)
This gets five stars from me. Short, sweet, and so wholesome. I would definitely recommend!