Act 1
Once upon a time Leopold a grand piano is paired with a young child Persephone and teaches her to play him. Persephone becomes a superb pianist, and every day Leopold and Persephone play together, and Persephone becomes a recognised virtuoso. Until one day Persephone is too old, and stops playing Leopold and dies and because of her death the house and Leopold are sold.

Act 2
Leopold is transported to a ship and placed on deck where he gives a concert. But the beautiful music distracts the crew who miss the approaching storm. And because of the storm Leopold crashed overboard and sinks to the bottom of the ocean. Where he is found by Octavia the octopus who begins to play him. Making Leopold happy once again, so he teaches Octavia and she becomes so good that they perform together and given concerts and become famous.
But because of the passage of time and the different life spans of octopus and grand pianos Octavia grows old and dies, leaving Leopold alone once more and very sad, feeling there is no meaning left in his life. He shuts down and withdraws.

Act 3
Then the tapping or tiny tentacles and the playing of a note on his key makes Leopold open his eyes again to the world around him and realize that there are many young Octopuses who want to learn and that there will be many more potential pupils. And finally Leopold accepts the transient role of a teacher who will teach many pupils.
And ever since then Leopold teaches in a music school under the sea helping them learn something new and enriching their lives as his, while knowing they will leave him.

The moral of the story is learning to embrace the impermanence of the role of teacher, taking joy from the intimacy and importance of these ephemeral but deeply significant relationships, and accepting the pain when they end.