I came across this recently when I was moving. I must have painted it 30 years ago, before art school. It turns out that "Arha & Penthe" are 2 characters from Ursula Le Guin's Earthsea Trilogy, from the 2nd book, The Tombs of Atuan.They were indeed best friends. I don't remember reading the book but it must have made an impression at the time. I think this must be the first "illustration" I ever did.