In the town of Moriya, with a population of over 30,000, there is a small shop that sells strange masks. However, these masks are given out for free to those the keeper sees as worthy of holding it. He says that the want for something is what he likes about them, weather they are pure or wicked. These masks, once in the hands of their owner, are given the ability to whatever the mask is that they wear, and can change their speed, power, or anything just by simply wearing the mask. These masks can only be worn by the user, and anyone besides the user wearing it could cause harm. Those who are pure would use their Masks to defend those who cannot and fight off Mask users who wish to use their power to do harm. Which will you use yours for?
Though these Masks are already powerful enough, one could advance the power to that of mass destruction if they so wish to, but they must insert the blood of another Mask user onto the mask to earn the power. Power strong enough to make their Mask that of the power of an Oni, and granting them any power that a demon would posses, hence the name Devil/Lived.
Unless you have the blood from a Mask user, do not make yourself overpowered.
Though you may be overpowered at this point, your only OP when you where the Mask. You're still human after all.
Do not bully others.
Do not try to solve your problems with a snap of your fingers. You must try to think of a plan to solve it.
Your character should have:
Nationality (You are not limited to just Japan):
Other (Whatever you want us to know about them)