A leech understands the art of borrowing time, at least in their minds. When in actuality they do not borrow it because their intent is never to return it,self-centered. There is however a place where they actually can return the time that they borrow and that is on the other side of life awaits eternity. Humans occupy a planet that will soon grow frost cold from the hearts of greedy men which it mimics. It has been the inevitable since times before. Thus as aliens we are here to influence to alter to change, all on borrowed time. The understanding is that 120 years into our stay, the borrowed time must be repaid. If we check out any earlier, well we just borrowed less, but still made good on our debt.