External Senia is a free-to-play anime role-playing game available on Steam that was created through RPG Maker. The game follows the story of Senia, a frightened yet determined girl in search of her "sister" who went missing three days prior to the start of the game.
- These events take place as flashbacks while playing the game.
When Senia was a young girl, she witnessed the death of her mother and destruction of her town by a demon. When the demon went after Senia, a surviving priestess ran to her aid and used her holy powers to banish the demon, albeit, temporarily. The priestess introduces herself as Magaleta and offers to take Senia in at the church, where she remained for several years. Practicing the art of swordsmanship, Senia secretly would want to join Magaleta on her demon hunting quest. As Magaleta heads out to find the demons, Senia begs for her to go, however, Magaleta declines and asks Senia to stay behind. Distraught, Senia follows behind her, stalking behind a nearby building at nighttime. As Magaleta uses her magic to defeat some demons, a man approaches from behind, preparing an attack. Senia jumps in between and takes the hit for her sister, much to her dismay.
- This section of the story is what the player actually witnesses.
Senia eventually reaches the Tower of Eternity, a place where she believes Magaleta is being held. After defeating King Slime, Senia is teleported to the Forest of the Fairies. After exploring the area, Senia finds a small fairy being chased by a spider, and helps her out. Senia explains to the fairy that she's looking for her sister, and the fairy responds she is looking for someone as well: the Queen Fairy Malphiq, who is the guardian of the forest. Malphiq went missing mysteriously three days ago, which prompts Senia to connect the similarities between Magaleta and Malphiq's disappearances. Senia agrees to look for the Queen in hopes of finding her sister. As Senia travels deeper into the forest, she stumbles across a violent adventurer who she manages to defeat easily, triggering another flashback. The fairy Senia met previously returns and wakes her up from the unconscious state and mentions that the adventurer was possibly possessed by "Eternity". After some more explanation of eternity and it's power, the fairy joins Senia on her quest.
Eternal Senia plays reminiscent of old-school RPGs, being able to equip items, opening chests, solving puzzles, and earning experience points and leveling up. In addition, combat happens in real time, with some of the weaker enemies dropping HP orbs upon defeat. As Senia levels up, she learns new skills useful in combat. Angel statues provide save points throughout the game. Senia can interact with objects by either running into them, or pressing the action button. After meeting the fairy in the Forest of Fairies, Senia is able to craft items using materials dropped from enemies or found in the wild.