Although Spike's talented piano skills are impressive, he's managed to keep his more outstanding abilities hidden for quite a long time, even from Rarity. That quickly changes one day when Twilight leaves for Canterlot to do some magical practices with the princess. Upon walking by the establishment, Rarity becomes curious about the melodious noises she hears, and later decides to request lessons to take up her afternoon, and in return, she plans on letting Spike learn a thing or two from her as well…

Spike is aged up in this.

Slightly coauthored with Draconian Soul.

Regidar did some editing. I'd link the account, but during this time, well… It's complicated.