These characters use, or are training to use, a whip in combat.
A whip is a tool traditionally used to exert control over animals or other people, through pain compliance or fear of pain, although in some activities whips can be used without use of pain, such as an additional pressure aid in dressage. Whips are generally of two types, either a firm stick device designed to strike directly, or a flexible whip which must be swung in a specific manner to be effective, but has a longer reach. There are also whips which combine both a firm stick (the stock or handle) and a flexible line (the lash or thong), such as hunting whips.
The style, length, material used in construction, and techniques for use vary between the types of whips, and only certain whips are actually practical for combat. Whips, when applied against a human adversary, work primarily through inflicting pain and fear rather than actual force. However, there are versions of the whip that can actually cut opponents and do severe damage (such as whips with barbs on the end). Most whips are capable of striking quickly, and the flexible ones can even be used to hit around obstacles.