Warning: Possible triggers mentioned in the chapter.
Abuse is heavily mentioned. A warning has been put in place when the abuse starts. A summary will be put next chapter, if you find this triggering in any way, please ignore the second half.

Lucy sat in the guild hall, at the bar to be exact. Clenched in her hand was a strawberry smoothie. A pink silly straw curled from the drink to her mouth. Fairy Tail's heaviest drinker sat next to the celestial mage. She drunkenly laughed at her, chugging the barrel of beer. The blue cat sat comfortably on her shoulder, eating a fish. The guild was it's normal self- loud fighting roared throughout the building.

Elfman picked up a table at launched it at Gray, saying "Strength is Manly!". The oak table crashed against a shirtless ice-make mage. He brushed off a few pieces of wood that rested on his shoulder. Gray turned around, throwing an ice attack towards him, though he dodged. The ice spear flew towards the door. The ice shimmered, as snow and shards fell from the flying weapon. The Ice Lance flew towards the doors, that was just opened.

A salmon-haired man had just opened the heavy doors as the ice spear flew towards him.

Time seemed to slow down as the guild realized what was happening. They froze at his reaction. Fast as lightning, he snapped his hand towards the ice spear. His hand gripped it tightly, as it stopped not even an inch from his face. He growled as he tightened his grip. The blue spear shattered as shimmered to the ground.

Gray's blood ran cold at the look Chaos gave him. The looked was full of fury and bloodlust. Chaos closed his eyes and visibly shook with anger.

He took a step forward, earning a frighted cry from Gray. Natsu growled again, as he opened his eyes. They were no longer his normal onyx colour, but a blood red. He smirked, hissing a few words. However, his voice was deeper and rougher.

"I'm going to kill you".

Natsu reached over his shoulder, clutching a part of his cape. He pulled the black cape over him. It wasn't until he threw it harshly to the side that they knew that he meant every single one of his words.

He sauntered forwards, earning frightened yelps from the guild. They scattered out of his way as he slowly strode over to Gray. The dark magic swirled off of him, whirling around the mage's feet.

Anyone who was within ten feet of the dragon slayer was thrown back harshly. They either landed on another guild member or crashed into the wall. For the mages that were hit by another memeber, they all fell over.

Lucy was sitting behind Gray, eyeing Natsu. Her eyes gazed over his heavily scarred chest. Seeing this, she got an idea.

She jumped off the chair, scurrying to the left of the guild hall. Natsu ignored her, assuming she was just getting out of the way. The dragon slayer continued his way forward, his magic flaring as if in warning. Gray looked horrified at Natsu. He put his hands together to innate an attack. "I-ice make..." He stuttered as he carefully watched Chaos. Said mage had his right fist aflame with a plasma blue flame. Even from the twenty-feet space between them, the ice-make mage could feel the heat.

He took a cautious step back as Natsu took several forwards.

However, something happened that no one expected. Lucy stood in front of Natsu, a brave look on her face.

Chaos scoffed at the brave stance of the Heartfilia girl. But there was something... off. Everyone else radiated fear, panic, and hate. All of the human's negative emotions were defined by 'chaos', and they all fulled his magic. Yet the mage in front of him showed no fear.

"Move" he growled lowly, still determined to end the life of the ice-mage who almost impaled him. Lucy stayed still, looking up to the furious dragon slayer. His gaze was pure intimidation, yet she stood her ground.

Annoyed, the dragon slayer rose a flame-filled fist. The next thing she did shocked everyone even more.

She reached up and slapped him across the face. the sound echoed throughout the guild hall.

Everyone stilled, looking at the mage in awe. Natsu himself was frozen, the flames on his fist burned quietly. After a few minutes of everyone remaining quiet, Lucy took a step back. There was a mark on his face, a red mark. It was Gray who then broke the uncomfortable silence. "Lucy, get out of there! He'll kill you!".

Natsu's reaction was equally as shocking to the guild. He said nothing, turning around. He walked over towards his disregarded cape. Still remaining silent, he clutched the piece of fabric, throwing it over his shoulder. The only sound that could be heard was his boots clicking on the ground as he left the guild hall. Lucy, along with the other members, started confused and amazed at the doors.

The silence remained in the guild hall, as Gray wondered how he was still alive.

Natsu walked through the forest, gritting his teeth. Never, in his several years of being a Fairy Tail member, had anyone touched him.

They were all terrified at even the sight of him. As he reached his isolated home in the woods, his calloused hand grazed his cheek.

His index finger touched the stinging mark. He grumbled as a flashback hit him strongly.

(Abuse starts here: please skip if triggering)

In the year X372, when a young salmon-haired boy was just four years old.

Natsu pushed himself against the wall. Tears streamed down his face as he quivered from his father. The muscular man stomped around the house, each step earning a whimper from the terrified Natsu.

He knew what would happen if he was found, and that's exactly what happened. "Natsu!" his father's authoritative voice boomed. "Come here now".

His voice was harsh and cold, just like his personality. Natsu hid behind the broken piece of wood that was the door to his room. He whipped away a tear, looking around for his brother.

Normally his brother would save him from their fathers' wrath. Suddenly the door was thrown open. Natsu let out a terrified whimper, giving away his location.

The other salmon-haired man stomped over towards Natsu. His hand gripped at Natsu's hair, dragging him throughout the house.

Natsu's father threw him out of the home. His little body rolled along the rough stones of the river bank.

The young boy attempted to push himself up, earning a kick to the stomach from his father. His father continued to kick him in the stomach, using his hands to keep him still. Once Natsu stopped fighting, the older man punched his son senseless. His fists felt like bullets as they continued to strike him. In the end, he could barely move.

The man picked up the boy by his hair, staring daggers at him. "You're worthless and no one will ever care about you". he grumbled, throwing him into the raging river. Natsu attempted to fight the rushing water, but the fact he didn't know how to swim. The water crashed over his head, dragging him under. It seemed to force him under, easily beating the joy boy with the water's power. Even the river saw him as worthless.

After a minute, he was pulled out. Natsu took a grateful breath of air. Though this moment was short-lived, as he was pushed underwater and held there. His father's hand kept a strong grip on the flailing boy.

Natsu gripped at his chest, sitting on his bed. He bared his teeth as another memory struck him, it was after someone warped him through time.

Back in the X770's, Acnologia's claw crashed down on the slumbering dragon slayer. "Worthless brat" he growled. Natsu hurried to wake and rose to his feet.

"M-morning father". he stuttered. The dragon's tail lashed at the child. It struck his chest, causing blood to spew from Natsu. The dragon slayer coughed, spitting blood.

The dragon didn't seem bothered by the warm, crimson liquid that drained from his son. Instead, his claw flew down onto him. He let out another cry of pain.

"You useless brat!" he roared loudly. The dragon of chaos bared his teeth angrily. "You let humans defeat you?" he flared his wings, blocking any exit from the cave.

His adoptive father was mentioning when a group of five human boys beat him in a fight. "Father, they-" he started to ramble. Acnologia roared for him to be silent. "You've failed me". He growled as he continued the rampage on his son.

Natsu shook his head. Growing up, he was beaten senseless whenever he showed kindness. He was always praised and treated for his bringing of destruction and death. Even when he was in Fairy Tail, no one ever touched him when he acted up.

So the son of Chaos assumed what he was doing was still 'right'. However, the stinging slap mark made him reconsider what the terms of 'right' are.

He clenched his fist in realization.

About 400 years ago, a mage saved him before he fell farther into darkness. Said mage was a blonde celestial mage by the name of Anna Heartfilia.

Natsu punched the wall out of frustration.

The Heartfilia's once again had begun to tame the chaos slayer.

Hello! What I meant by my favourite part is Lucy bi*ch slapping Natsu.
The abuse was a little hard to write 

Im really sorry for late update I have an exam in 4 days seriously and my moms forcing me to study

He's been on my shoulder the whole time while writing this.

Hope you have a great day/night!