Xi Sha

Xi Sha is a student from Xiahou High School who lives a double life as a guardian and protects normal humans from monsters. She is also the reincarnation of a demon lord that ruled the Underworld centuries ago. Due to her actions and relevance in the series, Xi Sha can be considered the deuteragonist.

Background
A century ago, two arrogant demon lords massacred the human world and the Underworld, killing thousands of people and demons indiscriminately. The two eventually met their demise when both humans and demons sent out all of their strong warriors to fight them and used multiple tactics against them, which they barely won with. After being killed, their souls resided in the Blood Pool in the Underworld and recovered for a hundred years, eventually they were able to reincarnate into two new demon lords, who are Che Yongtai and Xi Sha. They then spent years in the Blood Pool maturing and occasionally fighting each other before being released by Yan Sis to obtain the Heaven Crystal.

According to Shi Ji, Xi Sha's previous incarnation conquered the Underworld and was known as the "Queen of the Underworld". Her lover was Y'Shari, who ruled the Undeworld alongside her.

Personality
Xi Sha is often characterised as being arrogant, as seen when she constantly refers to most people as peasants (贱民) and to Che Yongtai as servant (仆人).

She seems to like food a lot, as shown when she fell in love with Ye Yan due to him wearing his Tired Chicken Leg costume, getting easily distracted or calmed down with food and easily bribed with food.

She only shows a soft side towards Ye Yan, who is the only male she is attracted to, as shown when she only blushes when around him and trying to get his attention. This causes her to constantly mistake and get jealous about Ye Yan's relationship with Huang Xiaoyan because she constantly mistake interactions between the two as something intimate.

Due to her petite figure, she is jealous and despises girls with a well developed body, causing her to constantly pick on them, especially during physical labor that she organises.

Appearance
Xi Sha has blond hair and turquoise eyes, she also has sharp teeth and a rather petite body, which makes people assume that she is younger than she actually is, which usually ends up angering her.

Before meeting Ye Yan, Xi Sha had relatively short hair and sported two long horns on her head, she also wore a suit of armor complete with a maroon cape. After coming to the human world, she ordered Xiao Jian to buy her a lolita dress which she wore for the rest of the series. After meeting Ye Yan, Xi Sha's horns fell off naturally due to demon lord physiology and grew longer hair. During the Double Devils arc she wore a yellow swimsuit. During the School Play arc, she dressed up as a dwarf from Snow White, a sister from Cinderella and ultimately as Zhu Bajie from Journey to the West. During the Ancient Time Tree arc, her body grew more mature due to a medicine made by Yun Zhonghe that allows her body to reach her prime state in life temporarily. She was also briefly rewinded back to her previous incarnation due to Yun Zhonghe's Rewind Blast.

Xi Sha reverted to her previous incarnation's form due to Y'Shari's Primordial Blood. Her previous incarnation greatly resembles her mature self, albeit occasionally appearing with orange-red hair for unknown reasons. Her hair reverts to its blond pigmentation whenever her current incarnation's consciousness overwhelms her previous'.

Abilities and Powers
Due to the reincarnation of the demon lord being inferior in quality, Xi Sha does not retain even 10% of the previous demon lord's power or intelligence. However, she still has superhuman strength, endurance, stamina and some other qualities that are only rivalled by Che Yongtai, another demon lord. In strength, she is able to break a game table using just her head and not even show the slightest discomfort, casually defeat numerous gangsters with just her hands, and bite through anything with her teeth and digest it. In endurance, she was able to take multiple hits from a fused Double Devil, who was able to defeat everyone else in the Department of Night in just one hit. In stamina, she was able to chase both Double Devils and attack them for a long period of time.

Equipment

 * Armor: Xi Sha wore a suit of regal armor with a maroon cape.

Normal Form (≤10%)

 * Mouth Enlargement: Xi Sha is able to enlarge her mouth to bite through things or to simply eat a large thing. This move combined with her extremely strong bite force can be quite devastating.
 * Whirlpool Bite (大口漩涡): An unknown technique that Xi Sha used off screen.
 * World Destroying Tornado (灭世大龙卷): Xi Sha creates a miniature tornado that pulls things towards her, since it isn't strong enough to damage people, she uses this move to create an opening.
 * Twin Fist Slam (双拳砸): Xi Sha concentrates energy into her fists and slams them down, it's actual power is unknown since Xi Sha only used it to create an opening so she can bite.

Prime State (100%)

 * Hell Flower (地狱花): Xi Sha summons a large Hell Flower that is harder than stone and uses its pistils to bind someone.
 * Finger Blast: Xi Sha concentrates energy on her fingertip and blasts out a purple ray of energy, only 20% of the ray's power was strong enough to break through Huang Xiaoyan's Protection Tag Barrage.

Previous Incarnation (100%)

 * Hell Flower (地狱花): Xi Sha summons a large Hell Flower that is harder than stone and uses its buds to restrain someone.
 * World Destroying Tornado (灭世龙卷): Xi Sha creates a large tornado that is able to tear a giant tree into shreds within seconds by pointing with her finger.
 * Monster Wind (赑风): Xi Sha can summon a tornado of "monster wind", which is a magical bright orange wind that blows into a creature's six entrails and penetrates its nine orifices, destroying its flesh and bones and disintegrating its body. Since the wind deals damage internally, spells that protect a user from external damage are ineffective against it.
 * Consumptive Learning: After consuming the flesh of a person, Xi Sha can read their memories, allowing her to learn about their abilities.
 * Purgatory Transform (狱炎变): Xi Sha emits immensely hot fire from her body, damaging people close to her.

Trivia
Xi Sha broke the fourth wall in Chapter 261 by saying "this manga is innocent, my ass!" after witnessing Huang Xiaoyan feeding an infant Ye Yan and mistaking it for their children.