Kingdom of Valla
Princess/Queen MikotoSecond princess of Valla, and later Queen of Hoshido. She can be pretty manipulative when she wants something, but is ultimately a good person who just wants a happy ending.
- Broken Bird: The repeated loss of her loved ones drives Mikoto to have more cynical views over the course of the story, as well as a hatred for those who took them from her.
- Fallen Princess: Goes from wealthy second princess to a destitute refugee when Anankos destroys Valla.
- Going Native: A recurring theme of the story. While staying in Hoshido, Mikoto learns many of Hoshido's cultural norms, which helps her keeps her Mysterious Past hidden. She later has to deal with this when her son returns from Nohr.
- Guile Hero: Overlapping with Manipulative Bitch early in the story, though she grows out of that attitude.
- Mama Bear: Nothing says protective like chasing after an entire battalion of Nohrian soldiers alone and on foot, then holding the king at arrow-point, to get your son back. Sadly for her, it's all for nothing.
- Rebellious Princess: Mikoto, in her early years, would sneak around outside the palace to consort with "Hydra", volunteered to go on adventures, and manipulated or broke the rules to suit her own ends. She matures out of it as the fic goes on.
- Silk Hiding Steel: Deliberately presents herself as meek and mild to hide how iron-willed and cunning she really is.
- Stepford Smiler: Her big thing is wearing masks—at first just to make people underestimate her, but then later pretend she's perfectly fine even as her Trauma Conga Line breaks her down. She even tries to uphold it while in the midst of a deep Heroic BSoD.
- Uptown Girl: For her first husband, Anankos. This ended up being a plot point when she had to manipulate her sister into letting them marry, much to Arete's anger. Later, her second husband Sumeragi was the Uptown Boy for her, since she was supposed to be just a commoner.
Queen Arete of Valla
Queen of Valla, then Garon's second wife and Queen of Nohr; mother of Azura; and elder sister to Mikoto.
- A Child Shall Lead Them: She ascended the Vallite throne at age fourteen after the untimely deaths of her parents.
- Badass Bookworm: Arete loves studying magic, would happily have become a magic researcher had she not been a princess, and spends part of her off-screen time trying to create a barrier spell to repel Anankos. And succeeds.
- Brutal Honesty: She's very opinionated and honest about it, not letting even familial love stop her from ripping her sister a new one when she feels the need is necessary.
- Fallen Princess: After fleeing her kingdom during Anankos's invasion, Arete ends up in Nohr and is forced to scrape out a living on the streets as a performer.
- Silk Hiding Steel: Like her sister, she's relatively calm and collected, but has an interior of pure, cold steel. Unlike Mikoto, her calm exterior is genuine rather than a mask.
Mikoto's first husband and Kamui's blood father, whom she finds as an amnesiac man and nurses back to health. After he regains his memories, he learns he was actually Anankos's soul given physical form, and helps Mikoto, Arete and their children escape. He then vanishes as his evil half takes over as the main antagonist of the story.
- I Can't Believe a Guy Like You Would Notice Me: Due to their differing social backgrounds, he's absolutely shocked when he finds out Princess Mikoto reciprocates his feelings towards her.
- I Want My Beloved to Be Happy: Knowing that he'll probably never see Mikoto again after his other half attacks, he makes her promise not to wait for him so she can find somebody else to take care of her.
- Insecure Love Interest: Before he regains his memories, he views himself as extremely unworthy of Mikoto, mostly in regards to the huge difference in social status. After he regains his memories, he still seems pretty uncertain about her feelings for him, since he knows exactly who he is and what he's done.
- Literal Split Personality: He's the soul (read: good half) of Anankos given a physical form. The other half is the Big Bad.
- Modest Royalty: Even after marrying Mikoto and becoming a prince, he still prefers his simple robes to elaborate clothes.
- Nice Guy: Respectful, polite, humble, and overall a swell guy.
Kingdom of Hoshido and Surrounding Territories
King Sumeragi of HoshidoThe ruler of the Kingdom of Hoshido.
- Boisterous Bruiser: He's frequently described as being loud, cheerful, and funny.
- Challenge Seeker: Mikoto even drops the trope name at one point. Sumeragi loves pitting himself against the strongest he can find, willingly undertaking the Rainbow Sage's trials and making annual visits to spar with the best warriors in the Fire Tribe.
- I Want My Beloved to Be Happy: Accepted Mikoto into his home without question and never once forced her to do the proper duty of a concubine, despite being in love with her, because he prioritized her happiness first and foremost.
- Uptown Girl: A male version, for Mikoto; he's the King of Hoshido, and she's a Fallen Princess masquerading as a commoner and his concubine.
Chief Kenta of the Fire Tribe
Leader of the Fire Tribe, and father of Rinkah.
- The Cameo: Makes one in Fire Emblem Fates: Aftermath, which is set in the same universe as Invisible Princess twenty-one years later.
- Defrosting Ice Queen: Male, platonic version to Mikoto. He's cold and suspicious of her when she arrives, but lets her stay, and at the end of her trip says the Fire Tribe "didn't hate having you here". Years later he shows up personally to her coronation and is much friendlier.
- Hidden Heart of Gold: Despite his gruff demeanor, he did allow Mikoto to stay with the Fire Tribe when she was lost on the surface with no strings attached other than a request that she respect their customs.
Duchess Hiromi of Izumo
Ruler of the neutral principality of Izumo, and mother of Duke Izana. Like her son, she's a bit eccentric and can communicate with the gods.
- Bunny-Ears Lawyer: She's a bit eccentric and party-obsessed, but she's also a skilled diplomat.
- Killed Offscreen: She was murdered by Anankos's soldiers, but it's not revealed until after the fact. The "crime scene" is described with brutal detail.
- Large Ham: You can see where Izana got his from.
- O.O.C. Is Serious Business: She drops the eccentricities and acts completely serious for once when she relays an important message to Mikoto.
- She Knows Too Much: Anankos had her killed because she started doing research on him after he sent a message to relay to Mikoto.
- Smarter Than You Look: She is shown to be quite adept at politics and diplomacy, despite her nature; her banquet wasn't just a frivolity, but her attempt at repairing relations between Hoshido and Nohr by forcing the leaders to spend time together in a neutral, peaceful environment. And it worked—she was able to make both Sumeragi and Garon willing to discuss peace.