There are thing we do and places we go where we can reasonable expect to be able to retreat from the world and not be bothered by other folks for awhile.
Sometimes they are elaborate rituals in which we cleanse ourselves of collective debris that accumulates on one's soul. Sometimes they are simple pleasures or chores that we generally take for granted until we find ourselves suddenly and rudely interrupted. Like being able to brush your teeth undisturbed. When we are denied these things our emotional displeasure is often out of proportion to the nature of the offense.
In my Equestria/ MLP dreamscape such an incident occurred to Celestia, and for her it was final thing that tipped her toward a decision of calling the Lord of Shadows bluff. Ever since Celestia has become aware of the Kingdom of Shadows she has searched to find a diplomatic answer to the problem. She would prefer to avoid a violent resolution to the situation, but she is not going to roll over and let the realm be overrun by horrors from the darkness. Still, she wishes to avoid dragging her subjects through unnecessary hardship if it could be avoided. However actions by the Lord of Shadows and his minions have made it clear that they do not view the ponies as being worthy of being treated with dignity, respect and courtesy.
After a long day of running over drills and planning contingencies [link]
all Celestia wanted to do was retire to her quarters. Jettison the trappings of her office. Give herself a good grooming. Brush her teeth and get some uninterrupted shut eye for a few hours, a rare thing for her recently, before diving back into it all. However even that was not to be when in the middle of brushing her teeth she suddenly found herself being addressed in her own bathroom by one of the Shadow Stallions [link]
who the Lord of Shadows was using as emissaries to Canterlot.
One minute it she was just trying to get her back molars clean and the next she had this oily black tire fire in the form of a stallion asking her if she was going to honor the request for negotiations between the two realms. No knock on the hallway door or even the bathroom door. No contacting a courtier to relay a message. No approaching a minister on duty that evening. No this would not do! If the Lord of Shadows was willing to treat the co-ruler of Equestria this way Celestia could only imagine how callous he would be to her subjects. This was going to end once and for all. She tersely relayed to the Stallion her desire to meet the Lord in two days time and two hours before sunrise in the planetarium at Everfree. With that the Shadow Stallion vanished leaving Celestia alone. Now alone again Celestia found herself staring in the mirror. Even the most calm and centered individuals needs to sometimes vent. Suddenly gnashing her teeth the toothbrush in her mouth snapped in two. Violently she spat the two broken pieces out, embedding one piece into the wall. Her mane and tail began whip and slash like flames in an inferno. Lighting in the bathroom started to change. Ominously.
Luna was also visited by one of the Shadow Stallions and after dismissing him she quickly sought out her sister. Upon entering her sister's quarters Luna was immediately aware of strong ozone smell and a harsh crackling sound. Accompanying this sound was a constant high power line hum coming from Celestia's bathroom. Harsh blue light poured out of the open bathroom doorway. Peering into the room Luna found her sister still standing there staring into the mirror. Her whole body was bathed in a blue Cherenkov-like glow. As Luna watched she could see the paint on the wall smolder and beginning to peel. The tile floor beneath Celestia was also beginning to crack and crumble. Luna was now aware of deep throbbing vibration that seem to be resonating from her big sister.
Clearing her throat with a small cough first Luna spoke. "I assume you to just had a visit from one them to?" Still looking into the mirror Celestia took a second before replying. "Yes." Was all she said. Luna looked down at her hooves then looked up again. "Sis, are you okay?'
Celestia slowly turned her head and pierced her sister with a stare that Luna had seen once before in her life. It was same look Celestia had had over thousand years ago when she decided that her only choice was to banish Nightmare Moon along with its prisoner to the moon.
"No I am not okay." Growled Celestia. Thinking for a second she spoke again. "How are you?" Luna rolled her tongue around in her mouth carefully deciding her words. "Celly, I'm fine but I am worried about you. Take a second and really look at yourself right now in the mirror. That is before it slags off the wall."
Silently obeying her sisters instructions, Celestia turned her head and stared again into the mirror. For several seconds she was motionlessly as she stared at her unblinking reflection. Then she closed her eyes and sighed. Like a Bunsen burner turned off the blue glow vanished and the crackle and hum subsided. When Celestia opened her eyes again they had the same warmth and love that Luna knew and loved so well. "Thank you Luna," Celestia said softly. Randomly scuffing one of her front hooves in a now thourghly charred bath mat Luna gave her sister a sly little smile. "I think someone needs to be taught a lesson in manners though sis." Celestia looked back grinning. "Yes someone does."