Answer:
They are toothy nocturnal immortals.
What has feet on the inside but not on the outside?
What is filled with air and sometimes a gas, tied to a string and often seen on your birthday?
Tall, I am young. Old, I am short. With life I glow. Anemoi is my foe.
Which one of Santa's reindeer can be seen on Valentines day?
If itβs information you seek, come and see me. If itβs pairs of letters you need, I have consecutively three. What am I?