Evil Requires Other People.
Could Robinson Crusoe be evil if he was alone? No sure about it, but I think not. What can you do to yourself without hurting others to be marked as evil, anyway?
Here's a thought: Taking your own soul.
Let's assume in this fanasty world that everyone does have a soul. Now souls are normally give to one god or another to take care of. I imagine that having a celestial power watching over your spot in the afterlife and in this life on earth comforting, and as such, has likely become something most partents do for thier kids, if the gods allow it.
But what if a person doesn't want that god to take care of thier soul? A person could become possesive of something as precious as that. The soul does represent where you're going to go after you die, controlling something is always a mark of wealth, what person driven to aquire wealth and the controll that comes with it doesn't try to prolong how long they can stay in control? As far as jewels and wealth goes, the saying is you can't take it with you, so do you think it could be possible to instead of taking the money to the afterlife, to try instead to bring the afterlife to the money?
So if you have a soul, and somehow you can rip it free of the gods, that would make you in charge of your afterlife, so naturally, why not postpone it till it's more appealing than the life you have at present?
But you are, in some manner, defying the gods thier livelyhood. A man who gives a farmer grain and then goes into the field and takes the crop denies the farmer food. If enough crop is taken, the farmer starves. Souls are more precious than grain, so won't that make the god that is denied a soul suffer more?
Of course, on retrospect, you do have to hurt the god to be evil in this way, so it does prove your point about evil has to hurt someone.
Well, trying to set a universal definition of "evil"

will be difficult because different culture have different interprtions of evil. In one culture, you make your home a place of safety to protect your loved ones from the evils that roam the land, in another, you are keeping your family as captives and denying them freedom. One culture says spirits are ancestors trying to help you and guide you through life, another says spirits are demons.
There are very few universal "evils" and also very few universal "goods".
Evil Seems To Offer More Evil gives you stuff, but doesn't good give you stuff too? Good gives peace, Evil offers control; Evil shows off pleasures everlasting, Good shows off ... pleasures everlasting; Good will give you all your wishes if you let it have your soul to take care of, Evil ... will give you all your wishes if you let it take care of your soul.
Seems like six of one, half-dozen of the other.
It does seem like to do evil, someone has to get hurt, but beyond that, that seems to be all I can come up with for the moment.