It was late at night, but one figure still roamed the halls of the School of Friendship. The school had been closed for hours, but this was nothing unusual. It was his job to be here after hours, after all. This was the school janitor, an odd unicorn stallion who spent all of his nights cleaning the corridors and classrooms that made up the sprawling campus. Every night, he arrived after the students and faculty had left, and he departed each morning before they returned. He hadn't even met most of the faculty. He'd only ever met Princess Twilight and the new headmare. Starlight was her name if he remembered correctly. The young stallion nearly cracked a smile as he noticed the humorous similarity in the names of the old headmare and her successor. He didn't smile, though. He hadn't smiled in a long time.
Occasionally, a student would come to the main school building after forgetting something inside earlier that day. The janitor just let them in and latched the locks again once they'd concluded their business. He would rarely strike up conversations with them. He wasn't looking to become friends with any of them. He knew better than to try. He'd learned that lesson the hard way. He didn't have many friends anymore.
[2 Years Earlier]
The janitor was roaming the halls picking up litter & cleaning up puddles of he-didn't-want-to-know-what until he reached the large doors that lead to the school's library. He heard an unfamiliar rustling sound within, and he was genuinely surprised when he opened the doors to reveal a young pegasus filly reorganizing the books.
"Golly, stranger," said the filly cheerfully, "I didn't know anypony was still here except for me."
"Well," the stallion replied in a stern voice, "It's my job to be here when other ponies aren't."
"Well, golly! I'm sorry good sir," whimpered the nervous filly.
The janitor chose this moment to drop the gloomy facade he'd been pranking the filly with and allowed a wide grin to spread across his face.
"I'm just messin' with 'ya, kid. Name's Knox."
"Cozy Glow."
Knox felt a stab of longing as he remembered the friend who had betrayed him, along with the rest of Equestria.
As his work came to a close, his spirits lifted a bit. Once again he found himself nearing a grin. He liked this part. One of the few things that brought him happiness nowadays was when he used his magic to disengage the locks on all the doors so the students could enter the main building. He didn't wait for the students to arrive. He never did. He just started on his short walk home. It was morning, and the sun shone high in the sky, but the first thing he would do upon reaching his home was go to bed in preparation for another hard night of work. He had just completed his favorite part of his job, but he he still didn't smile. He never smiled anymore.