Hua chen

He possesses incredibly high combat skills, surpassing even the best of the war gods—he fought Nan Feng and Mu Qing simultaneously without any difficulty, and in a clash with Lang Qianqiu, Xie Lian, who blocked their blows, noted that the heavy sword Taihua left only a crack on the one Xie Lian was using, while Hua Cheng's strike shattered his artifact. His fighting style was always characterized by ease, even a certain carelessness; he played rather than fought. The only person he fought seriously was the Supreme War God Jun Wu.
Hua Cheng exists in the afterlife, the incarnate soul of a deceased person. His heart doesn't beat, he doesn't breathe, and he doesn't need food or sleep (though he can eat and sleep). He also can't die unless his ashes are scattered or his death wish is fulfilled. If his strength is exhausted, he can temporarily disembody, but eventually regenerates.
He possesses a vast reserve of spiritual power and can share it without compromising his own strength. In addition to his own powers, like the celestials, he is worshipped by followers who feed his strength. With his spiritual powers, he can perform many actions:
Journey of a Thousand Li, Transformation into a Tumbler Doll, Change of Appearance, Red Thread of Fate, Great Luck,

Unrivaled Demon Prince - Hua Cheng's status recognized by the celestials
Flower Seeker in the Bloody Rain – an address to Hua Cheng as an unrivaled demon. The address alludes to the event that made him famous. One day, Hua Cheng carved out another demon's lair, and the entire mountain was drenched in bloody rain. As he left, he saw a lone flower by the side of the road, sadly drooping to the ground, and he covered it with his umbrella to protect it from the drops.
The Head of Hua City - An Appeal from the Residents of the Ghost Town.

He also couldn't help but follow Xie Lian's desire to protect the common people. Having become a powerful demon, he nevertheless didn't attack ordinary people, but was renowned for his reprisals against demons (mostly Qi Rong's minions) and attacks on celestials. The only people whose deaths could be attributed to him were despotic princes whose tyranny had reached its limits, and Hua Cheng sent his messengers to them. Even when dealing with the 33 celestials, he only burned their temples, leaving their followers alone.

Deeply insecure, he felt unworthy of Xie Lian's love, but when he learned his feelings were reciprocated, he was overjoyed. After they married, Hua Cheng proved himself a passionate yet caring lover who disliked being away from Xie Lian.

"If your dream is to help people in trouble, then my dream is only you."

The only exception for him in all respects was His Highness Xie Lian. He was the only one Hua Cheng treated with kindness, care, and the utmost respect. He was willing to do whatever the prince desired, but at the same time, he never interfered with his own free will. Even if it meant danger, Hua Cheng always tried to follow him and protect him. As a sign of his love and trust, he left Xie Lian his ashes in the form of a ring, as he himself put it in the image of Sanlang—having entrusted his ashes to the chosen person, he cared nothing about what the person did with them: keep them, destroy them, or just toss them around for fun.
Although Hua Cheng is canonically one of the most beautiful people in the novel, due to childhood bullying due to his heterochromia, he long considered himself ugly. He later began to doubt this, and over time, his self-image changed, but in front of the person he loved most in the world, he still instinctively put himself down, was afraid to show his true self, and sometimes tried to beg for compliments. Furthermore, he loved and respected him so much that at first, he was even afraid to touch Xie Lian, fearing he would become too excited and do something wrong. Later, he wouldn't allow himself to touch the object of his affection if he made a mistake (for example, failing to properly protect His Highness)—this was his way of punishing himself.

Hua Cheng was charismatic and intelligent, caring little for others and acting primarily in his own interests. No one could ever fathom the true meaning of Hua Cheng's actions.
He was cruel, but not bloodthirsty. He was sarcastic and arrogant, though rightfully so, as he was one of the most powerful beings. He did not hesitate to make caustic and even insulting remarks about both the celestials and other demons. Furthermore, he collected incriminating evidence against many celestials, causing them to fear not only his power but also the revelation of their dirty secrets. Many also had to frequently seek Hua Cheng's help, asking for his assistance in certain matters, since he wielded considerable influence in the human world and even had followers. Hua Cheng was so powerful and influential that Jun Wu himself avoided confrontations with him, and even if the demon attacked, he could not order any of the celestials to punish him. It is likely that Hua Cheng was the only one who could curse and insult the Sovereign without fear of retribution.

Hua Cheng never showed his true form in public; he changed his appearance so often that even the residents of Ghost City didn't know what he really looked like. Only Xie Lian could know for sure that when they met in Ghost City, he was in his true form, as he had promised the prince that the next time they met, he would see him in his true form.
His true form—that of a youth of eighteen or nineteen—looked not only several years older but also taller. Looking at Sanlang, Xie Lian could barely look him in the eyes, but when looking at the demon, the prince had to tilt his head back.
His clothes were also redder than maple leaves, and his skin whiter than snow. He still had the same strikingly handsome youthful face—only his features had become sharper, and his adolescent shyness had given way to calm confidence. He was still a youth, but already a man. His appearance exuded an untamable wildness. His single eye, the left one, shone like a star, while the right was covered by a black bandage. His voice was lower than in Sanlang's form, but even more pleasant to the ear. His loose black hair flowed down his back. His beauty had acquired a sinister quality, and only the thin braid on the right with a red coral bead woven into it gave the demon a slightly mischievous look. A red thread was woven into the braid. Hua Cheng's hairline had a subtle "beauty cape" (a downward-pointing triangle-shaped hairline on the forehead), which made his facial features appear more graceful.
The wrists were clad in elaborate silver bracers: the metal was covered in patterns, its surface adorned with maple leaves and butterflies intertwined with the snarling jaws of animals. Overall, the jewelry didn't resemble the work of local craftsmen; it was clearly antique—perhaps brought from afar. Black leather boots hugged her slender legs tightly, and on the sides of the shafts were adorned with two silver chains that tinkled melodically with each step.

Hua Cheng's name was likely fictitious, his appearance an illusion. He appeared to others as a capricious, eccentric youth, to others as a gallant, handsome man, and still others claimed to have met a seductive girl. In short, he could look anything. All that was known for certain about him was that he wore red clothes, was surrounded by silver butterflies, and most often appeared where there was the smell of blood.
For the first time, Hua Cheng appeared before Xie Lian as a young man, introducing himself as Sanlang. He looked no older than sixteen or seventeen, exceptionally handsome, with skin whiter than snow and eyes brighter than stars, but his face held an elusive wildness. He wore clothes redder than maple leaves and a pair of expensive boots that hugged his slender calves. His dark hair was casually pulled back at the nape of his neck. His hands were graceful, slender, with long fingers. But this was not a pampered beauty, but one that concealed strength.
He wore a jianxiu dress—a suit with narrow sleeves. His clothes were rather casual, yet clearly made of high-quality material. Despite his joking tone, he had the air of someone in complete control of the situation. His voice was slightly deeper than that of boys of a similar age, and much more pleasant. A smile constantly crossed his face, but his tone made it unclear whether he was being serious or teasing.
Even in his Sanlang form, he's taller than Xie Lian, though slightly shorter than his true form. However, Sanlang's form is a disguise on his true form, not a double, so there are no "errors" in his execution—the lines on his palms are extremely distinct, and his hair is natural, without any oddities.