Enurian is hesitantly given a PG-13 rating.
Much of Enurian's storyline revolves around the loss of humanity, dehumanization, and body horror. These feature most heavily in Lupinetooth's arc and affected characters (Quicksnare, Mouse-ear, and Xericstorm), as well as the affiliated deity, Helleth. However, it is alluded to in some other character's arcs, and so if you are triggered or squicked out by these themes, I recommend finding another story elsewhere.
Apocalypses, while not technically experienced by the characters themselves, is a revolving theme within the Enurian universe. The Imbroglio is the abandoned city of an alien race long-extinct, and many cats will roam this place.
While not called so by name, Lupinetooth's arc and affected characters (Quicksnare, Mouse-ear, and Xericstorm) revolve around a cult.
There may be mentions of violence, gore, or fighting, however, none are mentioned in graphic detail.
For reference, Enurian is inspired mainly by Blaseball, Terminal 00, and the aesthetics of the backrooms, and will have (somewhat) similar themes as these things.
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