There are tangible things in this world that anyone could see, feel, hear, or perceive in physical ways. So, what about the things that we can't interact with? Intangibles can be concepts, ideas... really just anything abstract that you wouldn't be able to have a conversation with.
Or, at least, not without the intervention of supernatural forces. There exist those who can influence reality, and through these means, they'll personify or use the power of the intangibles for any kind of purpose.
When a pacifist with no real motivations discovers his innate skill, he is forced to contend with these unimaginable forces that threaten his teenage school life. Is it really possible to protect his reality and live a normal life without fighting back?