Fun

Fun is what happens when you are doing something and are enjoying it.

These things are fun:
 * killing a Sue
 * playing in the All-HQ Australian Indoor-Rules Quiddich League
 * Getting completely drunk and singing karaoke

These things are not fun:
 * going through the mission so as to get to the Sue.
 * losing to the DBS team at Australian Indoor-Rules Quiddich (because they firmly endorse the down-trou rule).
 * Finding out your partner recorded you taking a go at karaoke.

"Fun" is also the recorded official word of Agent Acacia Bird of the Department of Mary Sues, the famed Assassin who is now, sadly, retired.