The Felbog Fang... what in the actual F**K is this thing..

Who actually thinks something like this is a good thing? How does one even determine how best to use such an item without pob and even then... how? Does it start counting down from the time the first curse is applied or are you not allowed to refresh any curses in order to let the duration tick down? Perfect example of how bloated and convoluted this game has become