Training and Activation.

It was around two in the afternoon on a hot summer day when Yong-sun finally convinced the nurses to let him step out of the hospital for some exercise. It was a combination of using his dashing looks and promising them that he wouldn't push himself too hard.

Of course, this was a lie.

Yong-sun planned to push himself as much as he could to gain strength. This was a promise he made to himself.

After doing some warmup exercises, Yong-sun caught his breath, closed his eyes, and started coming up with his exercise routine. The hospital yard was mostly empty as it was getting late so there weren't many onlookers there except the staff. That meant that distractions and obstructions would be minimal.

'Hm, judging from the fact that I don't see an EXP bar anywhere on my system, I probably don't level up. This means that I'll have to increase my stats by relying on Endless Development. Hmm, a good running distance should be 20km. If this body can't handle it, I'll just do 10. After that, around 500 push-ups and sit-ups, each, would do. Lastly, I'll train in my hand-to-hand combat and my swordsmanship.'

Yong-sun also wanted to test out a few more elements but he was in too much of a crowded place at the moment. He didn't know what kind of attention he would attract doing anything magic-related in a place like this. So, Yong-sun headed to the walkway in front of the hospital. This walkway actually surrounded the entire hospital compound so as long as he kept doing his laps, he would be eventually be done with his 20km run.

'And when I get to a secluded area, I can try to consume air. Let's see if that works.'

Yong-sun took a deep breath and exhaled loudly, with traces of steam exiting his mouth as he did so. But, he paid no attention to this.

WHOOSH!

Instead, Yong-sun boosted off down the walkway in a full sprint, running past everyone in his way like a speeding bullet. He intended to fully push his current body to its limits as even though he was inhabiting it, he didn't know what its abilities were.

[Two hours later]

Name: Park Yong-Sun

Age: 21

Class: Magic Swordsman/???

HP: 800

MP: 5/???

Strength: 14>18

Vitality: 14>18

Agility: 10>20

Intelligence: 15>17

Perception: 15

Passive Skills: Endless Development.

'Phew...that was easier than I thought. The nurses said the sun would be excruciating today but so far I haven't been anything but cool. Strange.'

Yong-sun sat on a lone bench behind the hospital drenched in sweat as he stared up at the sun hovering in the sky, deep in thought.

'I'm pretty sure I'm already faster than the best pure human athlete from my past world. I underestimated my current abilities quite a bit. Looks like changing to running 35km a day with ample increases in push-ups and sit-ups is the right option.'

But, as Yong-sun came to this conclusion, he still had something else that was bothering him. He looked down at his body evaporating the sweat with ease and thought, 'What is going on? The sun can't be that hot to visibly evaporate my sweat almost immediately. The sun actually feels warm...the heat feels nice.'

It was then that Yong-sun jumped up from his stupor as something suddenly clicked in his mind. With his ever-increasing intelligence, Yong-sun was surprised that he didn't come up with this answer sooner.

'Its heat! Of course it is! My body was giving me the signs all the time. The metal melting in my mouth, me breathing actual steam, and the evaporated sweat. Heh, not bad at all.'

Not wasting any more time, Yong-sun looked around to make sure no one was there and got up from the bench. Even as he did so, his hospital clothing started to slowly burn off. His natural body heat was already soaring to the skies. Now, he just needed to take the final step. He just needed to consume it.

'Now!'

Yong-sun opened his mouth and like water entering an empty dam, the heat in the atmosphere rushed into his mouth with reckless abandon, filling up all parts of his body. He quickly took off his hospital clothing and threw them to the side because if he didn't, he would have to walk back to his room naked. The heat was too much.

'Wait, something else is entering my body along with the heat! Is this...oxygen?'

To be clear, what entered Yong-sun's body wasn't just oxygen, it was completely pure oxygen that was siphoned out from the air. So, oxygen plus a ludicrous amount of heat and Yong-sun's magic as a substitute for fuel equaled...

BOOM!

Fire.

Raging red flames circulated around Yong-sun's body, bolstering and transforming it on a fundamental level. His muscles started to become much more defined, his lungs, now covered in flames, were becoming much stronger and if one looked closely, scales were being manifested on his skin. But, this wasn't the end.

BOOM!

The flames started raging even more as another explosion erupted from Yong-sun's body. The red, raging flames became pitch black as they surged around his body, entering and exiting every crevice. These flames were much more sinister than the last. They made Yong-sun feel an unquenchable thirst for anger and vengeance. It felt like even if he burned the world and eradicated all humanity, the flames still wouldn't be satisfied.[A/N: Chinese novel much?]

But, it still wasn't done.

BOOM!

The black flames became a sickly, emerald color that flashed with hints of silver in it. These flames felt...different, more focused than the last. The rage contained inside didn't subside, in fact, it increased dramatically but at the same time, it felt tranquil. A perfect explanation would be the black flames felt like they were meant for destruction and would force him to do so regardless of how he felt; the emerald flames felt as if it was meant for total and complete eradication of any bit of life the user deemed fit.

They sounded similar but the two were fundamentally different.

[Ding!]

[Title unlocked: Flame Of Corruption]

[Class change in effect...]

[Class has been changed from Magic Swordsman to Gehenna Dragon Slayer.]

[Starved Debuff has been removed.]

['Concept of Fire' Immunity gained.]

[Draconic Body has been unlocked.]

['Power Over Red' has been unlocked.]

*Whistle*

"My real class has finally been unlocked! Talk about a feeling of overwhelming power. Even my stats have been boosted once again."

With every breath Yong-sun took, a hint of sickly, emerald flames could be seen exiting his nostrils. Every step he took, the ground around his feet was left charred. Of course, all of this was only happening because he lacked control over his magic but it gave one the illusion that he was a God of fire that descended from the heavens.

Yong-sun couldn't wait to practice with his new abilities. He was much too excited at this new prospect of power to even go back to the hospital now. No, he decided he would stay and train there for the rest of the day, at least until he could control his natural body heat enough.

"Heh, stronger than me my ass. Shin-yoo is gonna flip when he sees this..."

---------------------------------------------------------------------------

Name: Park Yong-Sun

Age: 21

Title: Flame Of Corruption. {Enables use of the primordial emerald flames that existed before fire magic itself was created.}

Class: Gehenna Dragon Slayer. {All credit goes to Per. Check out her work on the fairy tail fanon. She's fire.}

HP: 1200

MP: 600

Strength: 23

Vitality: 23

Agility: 25

Intelligence: 16

Perception: 40

Passive Skills: Endless Development, 'Concept Of Fire' Immunity, Power Over Red, Draconic Body.

Class Skills: Gehenna Dragon's Roar, Gehenna Dragon's Infinite Iron Fist, Gehenna Dragon's Infinite Brilliant Flame.