ML accidentally meets a demon king from another world, said demon king happens to form a pact with him despite ML being a cultivation nobody and not at all worth of such a being.

MC happens to accidentally meet one of the best pharmacists in the world, said pharmacist happens to take him as his disciple because of MC's magical potential, yada yada.

MC needs to hide his special constitution, so he shouldn't run around too much.

Then he gets a magical bracelet that hides it, but only from people below a certain cultivation level, so he still needs to avoid bigshots.

Suddenly he goes to a competition where lots of bigshots will likely be present and everyone just seems to have forgotten about the bracelet's limitation.

The MC has a Yin physique that attracts demon cultivators. The MC's family is around these demonic characters, and they know about his physique. The MC and ML know the MC's family know about his Yin attribute. Yet, three paragraphs are dedicated to them trying to figure out why the demonic cultivator is after the MC, and they never do. Then, later in the story, they magically remember that this might be the reason the MC was targeted by the demonic cultivator. But, it gets worse. To add insult to injury, demonic cultivators can tell when someone with a Yin physique is in front of them. The MC even got a special bracelet to protect him, but it wouldn't work if the other person's cultivation was too high. Yet, the MC was running around in front of several demonic cultivators strong enough to see through the bracelet's protection, and none could tell. And before a reader says the ML's Yang physique makes it difficult to tell, this happened before they dual cultivated.

There were a lot of wasted opportunities to give the MC and ML more character depth and change this into something less formulaic. The MC was crippled in his last life. I think that would have an impact on a person's personality. Also, the ML was crippled at the start of the story, and the MC was blind. A seeing person goes blind and does not react? No moment to sympathize or comment on the man you're quickly falling in love with's situation?

The MC ends up in situations but shows no reaction to them. There were some emotions at the start when he was trying to figure out his situation just after transmigrating, but that stopped.

This quickly got repetitive because nothing was interesting about the characters or the scenarios they were experiencing.

Self-inserts are popular, so I can see why writers follow the trend. I'm fine with it, but stand-out works make the MC a blank canvas, but give the supporting character, especially the ML character development. This failed to do that.

This isn't really a romance novel. Romance isn't the focus, but it could have been handled better. The action/face-slapping is the focus. Those weren't written well, so everything became mediocre.

The MC was too dumb.

The ML was too smart.

Both the MC and ML intelligence fluctuated wildly depending on what the author needed the reader to know and understand. All the villains' intelligence disappeared as soon as the MC and ML showed up.

The supporting characters were also lacking. The whole South Coast arc made no sense. The Emperor and his Imperial court + The Mu family couldn't figure out there was something wrong with the grievances of those who had died until the MC pointed it out. This wasn't the first time they'd performed the ceremony since the war started, and there were no warning bells about the souls of the cultivators all being white.

I was also weirded out by how much emphasis was placed on the MC's beauty and the comparison to him being like a gorgeous woman. At times, it felt like the writer wrote a female MC but changed it to male later. This was poorly written to attract a specific female reader.