Evil is evil for many different reasons, it could be because of revenge, because it gives them a place in the world, or because of the money. In some cases it just depends on perspective, that is why...
If you only want to know answer in yes/no, then its, yes. Do read more as this will help. Becoming Christian does not insulate/immunize one from evils and therefore; a Christian can have evil and may...
maybe. maybe not. it depends on what kinda evil you're talking about. but actually, n general, i think it's ok unless evil picks the fight with you first.