Howd it start?

It was just a normal day like any other, or wasnt it? As a colegue student Kai was on his way to school. He saw a little child passing the street nothing extraordinary but, the child was about to get hit by a car. He charged toward and pushed the kid aside causing him to get hit by the car. 

He eventually died....

He opened his eyes and found himself in a dark red room. "Is this Hell?" he quietly asked himself

A voice from behind him spoke. It was a womans voice. At least thats what it sounded like. "You are wrong and right! This is your chance to continue living, BUT you have to pay a prize!"
That was some shocking news right there to him. He could choose to either die or live but pay a prize. He didnt hesitate tho he instantly chose to live again even for a prize!

"So what will the prize be?"
"Hehe~ You didnt hesitate did you. The prize is completing some levels of our games! You have to survive them all to get the prize!"
"How many are there?"
"Just a few ya know....few hundreds...." 

She had a meschievous smile on her face. She was the devil herself! Yes she aparently had black wigns and dark green horn so she is litterally the devil herself. Her bright green eyes were full of excitement and evil.
That answer shocked him. A few HUNDREDS?! But he took it anyway because he wanted to live. I mean who wouldnt? 

"Oh and also. I will be your system trought the levels from now on."

She added.

And thats how our Shy but Brave white-fluffy-haired boy met his devilish system.

Description of our pretty characters:

Starting with Kai. He is a brave young man at the age of 18, also hes shy too. You know how i mean it. He has middle-lenght white and FLUFFY hair. Pink eyes and darker skin. 
He likes to wear a big white shirt with short sleeves and baggy long black pants.

Then we got the system. Shes a devil as it was already said with geeen skin (her horns are the same color as her skin), bright green eyes and shes a red-haired person with short straight hair and as i mentioned earlyer she has black wings made with feathers. She also wears a black croptop with those weird sleeves. (shes on the cover if you didnt notice)