Create a subrule in the rule Hair titled Neck Hair. It shall contain the following text:

Any time after the time switches from Nighttime to Daytime, any villager who was the target of any werewolf has a 45% chance of the hairs on the back of their neck standing up if the villager is still alive. If this happens, the mayor shall send the villager an email stating such in any way the mayor deems appropriate. The villager shall not be told any information regarding the identity of the werewolf or how many were targeting the villager.