It's wrong to use your illness to your advantage.
Kati has cancer, it's a slow moving cancer but a scary one all the same, and she's in an argument with her friend.
Kati wants to win the argument.
Kati uses some logic to outwit her friend in this argument.
Kati asks her friend how she can be happy fighting with a person who has cancer.
Kati's friend admits that Kati was right, and they go back to normal.
Kati's friend feels very guilty and apologizes, but doesn't really seem to be wrong in the argument.