This is my horse OC, Unnamed OC! Creative name, isn’t it? I thought it was pretty clever. (I seriously have no idea what to name her lol.)  
This unicorn mare is an antisocial one, due to her awkwardness, but she is a talented writer and quite good at magic as well. She’s interested in all things odd in magic, like unknown potions or strange incantations. She’s also quite well versed in ancient Equestrian history, or as much as there is to know about it.  
She was born in Canterlot, yet she wasn’t quite happy there. While initially bad tempered and reclusive due to past failures, her lack of hope in herself and the world led to an encounter with Twilight. Although initially she distrusted all who crossed her path, including the princess and her intentions, the two grew on eachother and blossomed into a close friendship. Twilight helped her see the good in herself, as well as the ability to trust other ponies and to see the world through a more fair lens in which everything isn’t out to get you, as she had first assumed. While she’s not an Element of Harmony or anything of the like, Twilight doesn’t see her as any less special. This new treatment allowed her to grow into a more energetic, curious, and happier pony. She’s also quite funny as well.  
Being a huge book nerd, she loves coming over to Twilight’s Castle’s library to discuss the latest release or old pony philosophy. They both enjoy stargazing together, reading of course, chatting about the nature of life, sharing spells, and Unnamed Horse OC has never been happier. She was one day invited to live in Twily’s castle, and of course she agreed excitedly. Over time, they started avoiding eachother because they are both nervous idiots that don’t know how to deal with loving someone. When her brother Shining and his wife Cadance came to visit one day, of course the Princess of Love noticed that something was off (and shipped it really hard). She dropped Twilight some hints, but she didn’t seem to take any of them. Soon Cadance left to return to the Crystal Empire, wishing her sister in law good luck, though Twilight didn’t know exactly for what. One day, Twilight nervously came up to Horse OC and apologized for being absent so often. Horse OC said it was okay. She was avoiding Twilight herself, though she didn’t tell herself such. She doesn’t quite get social cues that well, and assumed Twilight was getting tired of her, not realizing she was doing the same thing as her. They talked for a bit, and Horse OC told her how she saw herself as trash. She said that Twilight doesn’t have to be around her if she doesn’t want to, and that she’s sorry. Twilight was confused as to what she was apologizing for, and told her how loved she was. She noted that she would always love her. Horse OC was shocked and super heckity heckin happy. It became more clear to both of them why they were acting weird. She deeply loved Twilight too. There were cuddles and smooches and there was a wedding and I CAN LIVE IN MY LITTLE FANTASY LAND, SHUT UP MOM.
 
I’ll update her appearance as I live my life and figure out more of who I am, but for now, enjoy a shameless self insert OC.