A progressive holding-period transaction tax is a fee imposed on the selling of financial instruments (e.g. stocks). The less time that the asset was held for, the higher the tax. 

You are Arwen, a magical immortal elf in a land where magic is fading. If you stay in this land you will eventually die. You have fallen in love with a human, Aragorn. Although Aragorn is blessed with extraordinarily long life for a human they will likely die sooner than you.

Most elves are currently leaving for another location where magic still exists and they can continue to be immortal. If you do not leave now there is no option of leaving. Aragorn can not come with you.