Sothis

Sothis is a character from Fire Emblem: Three Houses and Fire Emblem Warriors: Three Hopes. She is a mysterious girl that only Byleth can communicate with. She possesses a Major Crest of Flames. Despite her youthful appearance, Sothis speaks and acts as though she were a grandmother. She is frustrated at her inability to recall her past. She is usually sleepy, especially in the earlier chapters of the story and sometimes dozes off or fades during conversations. In the times she is awake, she offers commentary and questions the state of things, providing advice to Byleth on how to proceed. However, despite being a passenger within Byleth, she sees herself as above them, and sharply admonishes them when they respond to her with comments she deems foolish. She demands a certain level of respect despite the fact that she is ultimately powerless on her own as she must use Byleth as a means to interact with the outside world, albeit in a limited manner. In Warriors: Three Hopes, because she doesn't awaken until years later, Sothis seems to have more of her memory and knowledge, particularly by recognizing that Shez's powers are Agarthan in origin. Because of the latter's presence, she is also more willing to wield Byleth's body when necessary, but has no desire to retain control outside of certain situations, as she does not wish to erase Byleth's individuality in the process.