Okay, a lot of people have been having trouble with the character exercise, particularly with the exact meaning of 'thwarter'. The 'thwarter' thwarts the STORY, not the character: he or she deflects, shocks or bends the storyline. Let me clarify with an analogy from Newtonian physics.
Our protagonistic will, given the shape of their life and personality, either remain at rest or continue in motion with uniform acceleration in a straight line, right? Let's call this person A. The straight line is where the story is headed if nothing intervenes (usually a very boring direction)
Now let us introduce another person into this universe. Let's call them B. B can do the following:
1. B can attract A. A will curve towards B, and will then either attain B, or be thwarted by circumstances and remain frustrated.
So a new love interest, or a long lost parent, or a rich man to rob, or a new baby, or an escaping spy that A has to catch, or a gay man he's secretly attracted to, could be this kind of B. Actually all objects of love will be in this category.
2. B can repel A. A will move away from B and from his old line of movement, and either escape or be prevented from escaping by circumstances. A could also attack B in an effort to get back on track, or simply avoid B and solve the problem on his own.
Examples will include an overbearing mother, a jealous boss, a spy hunting him down, a wronged lover, an unwanted child, an enemy soldier, a besotted but unattractive lover, a rapist, or a terrorist who hijacks B's plane, or a man who steals his woman, or anything that does him harm and needs to be neutralised. B need not be doing this specifically to target A; it might be a by product of something else, but A will experience it as a personal effect. A could either rise above it an attack the root or take out a personal (deserved or undeserved) vendetta on B.
The reason why I want you to do the characters in pairs is that it makes it easier to work them into a story. A character in isolation isn't story material; two characters have to be.
