it will fall off on its own when it starts to suffocate as a result of the petroleum jelly, however unless you catch it and kill it it most likely will not die. you want it to die. since you are using the petroleum jelly method i would recommend keeping an eye on it and testing it with tweezers every so often to see if has loosened its grip. as soon as it feels loose you can go ahead and remove it and see to it that it gets effectively squashed.