Blueblood isn't insane, Lulu!
Ah, Blueblood...Never stop being you!
This thought came to Celestia as she watched Blueblood stalking Luna, the latter of which had no idea that there was a pony following her. I'll have to bring Blueblood back to life after Luna is finished smiting him to tell him that he has very nice and tidy spellwork. Despite how carefree and charming he could be, Luna sometimes found it hard to connect with her nephew, most likely because he did some of the most insane things that most ponies would never dare to even imagine.
One such incident was of Blueblood bungee jumping off the highest tower in the castle. To this day, Celestia never figured out how Blueblood managed to climb up the tower, let alone find the cable and harness, and it took a small rescue crew to rescue him (apparently, the reason he did this was to spy on the female royal guards shower room, as shown by the binoculars he was holding at the time of his rescue, and where he was facing). Another incident that Celestia found hard to believe that Blueblood would ever do was overpowering her guards, going through the trap infested hallway, and even knocking her out with a swift punch (to be fair, her eyes were closed as she was about to take a bite of a rather delectable pound cake), and that was all to get to her sock drawer. Her sock drawer. She still didn't know if she ever got all her socks back.
Now, she was watching her nephew sneak up on her unaware sister who was blissfully taking a bite out of a moon pie. Unfortunately for her soon to be startled sister, Blueblood had a megaphone in his grasp. To ensure that her ears wouldn't get blown out, Celestia had donned a pair of earmuffs. Although she wanted to warn her sister, she did admit to herself that she wanted to see what would happen. Besides, I told Lulu to stop eating moon pies; this'll just be her 'just desserts', heh heh! Smiling at the terrible pun she made, she watched as Blueblood finally stepped close to Luna, lifting the megaphone to her ear...
Something's not right here. "Erm?" Luna turned around, only to get startled and jump up through the ceiling (after this incident, the phrase 'Jumpy as a cat' was tossed at Luna mercilessly) when Blueblood began screaming the Equestrian national anthem through the megaphone.
Celestia, meanwhile, was laughing up a storm, and Blueblood was grinning stupidly, not realizing the heap of trouble he just got himself into. That was about to change, though. With a rather loud thump, Luna impacted the floor (causing a rather comical impact hole in her shape roughly six inches deep), groaning and holding her hooves to her ears, clearly in pain.
"Ow...Tiiiiiiiiiiia...What did I do to you...?"
"It wasn't me, dear sister, it was Blueblood."
Puffing his chest out in a mockery of certain birds, Blueblood proudly proclaimed it to be true. "That's right! It was me, all me!"
"You're insane, Blueblood!" As those words were spoken, Celestia made a 'tsk' sound, looking at her sister with disapproval.
"Blueblood isn't insane, Lulu!"
While I do enjoy my dear nephew's antics, sometimes they cross the line! "Sister, if what you've told me of Blueblood is true, he must have some streak of insanity in him!" Upon hearing those words, Blueblood turned around to face Celestia, who was pointedly looking away.
With his curiosity suddenly peaking high levels, he knew that he had to satisfy it before it got out of hoof. "Auntie Tia, what have you told auntie Lulu about me? I'm curious as to what you've told her!"
...Well, what has Blueblood done that isn't insane? Hmm... After a bit of pondering, Celestia decided to tell her sister the most 'tame' of what Blueblood had done, but even so, most of what he did was...Absolutely ridiculous regardless. "Well...There was the time you put ketchup packets underneath those little bumpy things in the royal guards' restroom..."
How could I forget?! Blueblood's eyes brightened up, and he laughed as he remembered that incident. "Ah, yes! I remember that incident; about half the royal guard was chasing after me!"
Really? While Blueblood was laughing as he remembered that day, full of angry, ketchup stained royal guards, Luna raised a brow at her sister. "That's still insane, Tia."
"What?! That was probably one of the more tamer things that Blueblood has done!"
"Yet he still created an incident where half the royal guard was chasing him! In fact...Has he done anything where he hasn't been chased by the royal guards?"
Of course! "There was the one time he was chased by the elderly and was charged afterwards with thirty restraining orders."
What in Faust's name...? "Do I even want to-"
"No."
"Let me rephrase my question, Tia. Has there been any time where he hasn't been chased by anypony?"
"Well...Only if he's caught."
"And that happens...?"
"...He's always caught."
Triumphantly, Luna raised a hoof in the air, while Blueblood tried to think of a time where he didn't get chased by an angry mob of ponies. "Ha ha! He is always chased by mobs and is guilty of doing dastardly, insane things! Admit it, Blueblood is insane, and if you think that false, he is at least a little bit out of his mind!"
Celestia tried to counter that, but there was nothing that came to her. Sighing, she nodded, accepting defeat. "Blueblood, you are a little bit insane."
After that was said, an explosion rocked the castle, and Celestia threw herself on the floor. "What in th-"
Her words cut off as Blueblood cackled with glee, and rubbed his hooves together. "I set off a soap bomb in the royal guards' barracks! Since I'm always chased by a mob, one should be after me right now! I'm surprised they aren't after me already, especially since I made some graffiti on the front door that said 'Blueblood rules, royal guards drool'! Well, bye, aunties!" Blueblood quickly ran out of the room with surprising speed, no doubt gained from constant mobs chasing him.
Celestia looked over at Luna, who looked back, and the two shared a moment of silence before wordlessly chasing after Blueblood.