Based on everything we have seem so far, i'm going to guess giving someone your feather is the ultimate "I love you" for a celestial or it has some become a slave for that person meaning. If any of those is correct, the Duke's reaction makes perfect sense.
Based on everything we have seem so far, i'm going to guess giving someone your feather is the ultimate "I love you" for a celestial or it has some become a slave for that person meaning. If any of those is correct, the Duke's reaction makes perfect sense.