Kretos the strongest demon lord, couldn't feel anything as his consciousness seems to be adrift in the abyss. He couldn't feel his body, nor could he feel the mana surrounding him. The only thing that he could do at this very moment was think.
'So this is what happens when you die... It's nothing but darkness. I always thought the afterlife had even more glorious battles, but it seems I was wrong... Still, in the end, I did get my final wish. I finally knew defeat, and I was able to die the same way I lived, in a glorious soul-shaking battle. Who knew that my eldest son, who was so much weaker than me, could pull that off. Well, that life has ended, I guess all that's left to do is sleep, the eternal sleep.'
At the very moment Kretos decided to rest for eternity, it was as if somebody heard his thoughts since at that exact moment a shining light flashed inside the abyss. The next moment, Kretos was somewhere with a wooden roof. He then noticed that he could once again feel his arms and legs.
He couldn't understand what had happened to him. One moment he was dead with nothing but his thoughts to keep him company, now he was in someplace with a roof, and he could feel his body functioning again.
Kretos tried to stand up but was unable to. He couldn't find the strength to stand. His sense of smell was also not functioning well. He then proceeded to feel the mana in his surroundings, a demon such as him was finely tuned to mana, but the mana he was supposed to be feeling was only the element of darkness.
Yet at this very moment, Kretos could feel all six elements, fire, water, earth, wind, darkness, and even light. This was something new for Kretos, which shocked him. The only being he knew that could harness all the elements of mana were humans.
Even the elves could only harness the elements of earth, wind, and water. Demons could only handle darkness, Celestians were only capable of harnessing light, and swordians well they're basically unable to harness mana in the first place.
It was at this point in time, Kretos lifted his arms he finally noticed that his arms were small and dainty.
This was not the arm of the supreme overlord, this was the arms of a baby.
Kretos tried to speak but was unable to. It would seem that his body wasn't developed enough to do such a thing.
'What the hell is happening? Damn it!... Wait what is this? Why does it feel like I can't control my emotions?... Okay, I need to calm down... I am Kretos the strongest demon lord, I died at the hands of my eldest son, for a few years now I was adrift in an abyss like place. While contemplating about the end of things, and thinking of the eternal sleep a white light flash inside the abyss, and now I'm in the body of a feeble human baby.'
Kretos was in a state of confusion, he couldn't comprehend what had happened to him. How come he was a baby? Not only that, how come he was a feeble human baby?
Was this some kind of punishment from those foolish Gods? Are they punishing him for slaying millions of humans? Even though they were the ones who attacked first, now he was being punished for defending himself?
Well at first he did defend himself from the attacks of the humans, but after a few dozen years, the humans would attack him again. They did this because they claim he and his race are evil. But that wasn't how it always was, at first they attacked because the greedy humans wanted more territory, later on, they kept on attacking the demon realm, claiming that he the demon lord kept on killing them for no apparent reason.
So after a few hundred years of repeatedly attacking him. Kretos finally snapped, and initiated his own attack, wiping out most of humanity.
'Well, they did strike first.' Kretos thought once again irritated with the Gods, for making him into a greedy human baby. At least he could still tolerate the cowardly elves, even the Celestians were better than humans since their only problem was they think they were the holiest of all creatures. Actually, if he was going to be reincarnated and couldn't be a demon, he wanted to be a Swordian. That race was a race literally made for battle, he and them even in his past life got along quite well.
While he was thinking of such things, Kretos suddenly felt hungry. It was an abnormal feeling since the hunger was actually hurting him. He who had survived years of war without eating not even a single grain of rice, was now in extreme pain for not being able to eat for a few seconds? This was another reason why he hated those humans, they were so greedy yet they were so weak as well.
He without his own consent started crying. He couldn't stop, even though he wanted to, he just kept on crying. After a few seconds, a woman with long black hair appeared and picked him up. Since demons and humans looked alike aside from having horns, Kretos thought that this woman who was most probably his mother in this life was actually quite pretty looking.
His supposed mother, then slid down a part of her dress around the chest area, revealing the thing that would feed the newborn Kretos.
...
After a satisfying meal, in what seems like a few minutes later Kretos started to defecate. Which resulted in him crying unconditionally again. While his human mother was cleaning him, Kretos started to think that not only was living as a human irritating, living as a human baby was a nightmare for him.
Also, he couldn't control the feeling of drowsiness, as he kept on sleeping. The woman who is supposed to be his mother kept on saying something, but her words were incoherent to him. The only thing he could somehow understand was the word, Ren. That must be his new name, his name as a human.
His sense of time was gradually being distorted. At this point, Ren felt a big strong hand had carried him. The person who was carrying him was smiling in a silly way as he held Ren in his arms. The man was equipped with weapons, a bow, and a knife. This man who had suddenly kissed him and his mother was most probably his father.
So just based on his own assumptions, Ren concluded that his father was either an adventurer or a hunter. Once his father held him in his arms, Ren felt something warm growing inside of him. This was a feeling he had already long forgotten. This was the warmth of having a family. Unlike his demon family who only respected him because of his power. This was a family that felt like it truly cherished him, simply because they were family.
'Hmph, maybe being a human whelp, is going to be okay after all.' As he was thinking such things, Ren was slowly feeling sleepy, and like his pooping and crying, he had no control whatsoever, as he fell asleep.
This was how the strongest demon lord, started his first day as a human.