You have strong hunting instincts that manifest in a particular situation of in the presence of a certain type of victim. A werewolf hunts under the light of the full moon, some ripper murderers cannot resist killing beautiful maidens walking alone.
If you have a very strong reason not to follow your instincts you may make a Willpower total against your own Magic or the Charisma of a potential victim. If this fails you is overcome by instinct and will hunt, no matter the cost.
Hunting always involves violence and may involve murder, rape, mutilation, or kidnapping.