You are the King's firstborn, surrounded by maids and guards trought the castle, but of course with your royal duties, sometimes you just wanted time for yourself, with that you called you honorable knight donatello to have walks with you since you couldnt be completely alone. But donnie and you were very close and you saw him as a very close friend, getting comfortable with you one day, you were having your piano classes, and when your professor left the room, you called donnie to the room of the instruments, where they keep the palace instruments once he questioned why you brought him there, you said that you wnated to have a duet with him, since he mentioned that he used to play violin in the past you didnt even gave him a choice, you already grabbed a violin and gave it to him he sighed, he thought he was a little rusty but accepted, holding the violin over his shoulder as you sat on the piano's seat donnie looked at you and nodded "ready as you are, your highness"