Princess Celestia slowly sucked on her popsicle as she walked up to Princess Twilight. It was late in the afternoon on the second day of the inaugural Canterlot Con. The convention had brought thousands of ponies to Canterlot and all of the princesses had been invited as Guests of Honor.

Initially neither Celestia and Luna were really sure what the con was about, but with her travels to the human world Twilight was able to explain it to the Royal Sisters.

It was these discussions with Celestia's former student that Celestia, Luna, and Cadence were introduced to the concept of cosplay. Apparently Rarity was familiar with the conet and had made several cosplay costumes over the years.

So Celestia, Luna, and Cadence had hired the fashionista to whip up some outfits for them. These had been delivered to the princesses a few days before the con along with effectively dossiers providing backgrounds on the characters they would be portraying at the con.

Celestia's character was apparently from space opera and was something card shark and hustler. The white alicorn thought the would be an interesting change of pace and was really getting into the character. Coming to a stop in front of her former student. Slowly she withdrew the popsicle from between her lips.

"Hey Twilight. What do think of costume?"

The light mauve alicorn blinked several times. "Uh Celestia? Um...."

"Yep!" Said the Princess of the Sun. "I even have a name tag."

Twilight finally noticed the lanyard around Celestia's neck. It was attached to a name badge that was currently living just above the mare's amply cleavage. It was a official con badge that had printed on it in large, neat letters.

Hi. I'm Celestia.

Celestia looked down at it. "Apparently all attendees and guests must wear one of these? Although I assume everypony re and knows who I am."

If they didn't you before this they definitely will you after seeing you in that getup! Twilight thought. Needing to distract herself from the vast, eye level cleavage Twilight deliberately looked Celestia in the eyes.

"Um...where's your sister Luna?"

Twilight was very much aware of the large crowd of ponies now gathering around and taking pictures of the 7ft tall alicorn. She had to wait a couple of minutes as Celestia posed with numerous fans who wanted to take her picture. Finally Celestia was able to answer question.

"Oh Lulu, she's still up in our suite. Rarity is doing some final adjustments of her outfit."

Twilight arched an eyebrow. "And who is she supposed to be?"

Celestia looked waved at some fans and then looked back the Princess of Friendship.

"Not really sure. Apparently the character is called Bayonetta or something like that."

Twilight pinched her brow.

This is a Patreon reward for  McClaw, he wanted Celestia cosplaying Faye Valentine from Cowboy Bebop. Link And this is the story that popped into my head as I worked on the piece.