A person who is up to no good; a rogue.
A person without a means of support; an idle, worthless person; a loafer; a person who is ineffectual, unsuccessful, or completely lacking in merit; a good-for-nothing.
Showing the characteristics of a ne'er-do-well: indolent, worthless, or roguish.
One who enjoys creating trouble for others by provoking controversy, for example by revealing facts that others would prefer to keep secret.