I had this thought the other day, I was hoping someone could tell me how feasible it is.

Say you're having trouble with a psychic leech. And say you notice how it drains you. Could you not scare off the attacker by letting him suck off all your negativity?

Imagine you were a leech, you find a good target with plenty of energy, and you begin to feed. You feel good at first, then before you know it, you feel like crud. You realize you're sucking in the wrong kind of energy, so you try to stop the connection. But you find your target is forcing it open and dumping all her negativity on you. Your victim leaves the encounter feeling happy and vibrant, and you feel like someone took a heaping steamy dump on your leeching spirit.

Likewise, it could work by sending extremely positive, loving emotions. I'd imagine a black mage would have a tough time being evil if he just sucked in a massive dose of love or enlightenment.

I could be way off tho, I don't know much about magic.