Ayavita is an undine friend of Ambrose and David. David meets her when he travels back to 1901 to see Ambrose. Her domain is the sea and she comes to shore to speak with them at Foreness Point.
She has psychic gifts and in Volume 2 declares that there will be a time in the future when they need her help.
Ayavita is in love with a young human man who is fighting in the Boer War and anxiously awaiting his return.