A cheater is the direct opposite of a Honorable Villain.  These villains have no sense of honor.  For example, adulterers will cheat on their spouses and/or their (Boyfriends/Girlfriends) with another man or woman with no sense of remorse, damaging their relationships.  Cheaters will always get the easy way out of things instead of working hard of getting their ways.  They will even commit fraud to get their ways.