This rule exists to protect a characters playability and the player's investment of time and effort and attachment to the character. It also exists to keep a player from being unfairly subjected to factors that may render the character, well, unplayable. In this manner, the rule provides insurance of a form to the player of that character that their assumed hard work will be respected, and will not simply be unreasonably confiscated.

However, this option should be invoked only in the most extreme cases, for example, death, and only when it is appropriate. It is not here for you to irreverently disregard other characters' powers and attacks that you just don't want to be subject to. IC actions have IC consequences. If you wander into a fight scene, watch forever, and then jump into the fray, don't suddenly decide you don't want to be attacked by one of the parties present. That is -not- what the spirit of the consent rule represents.

If a situation arises that fall under the realm of no-consent, you simply say 'no' or 'I don't consent to that' or some equivalent. Be forewarned that it is entirely possible that they party to whom you say this will lodge a complaint against you for doing so. Be very very careful about why you invoke this option.