Reep
A non-sophont animal native to Narnia.
The reep is winged and mouse-like, a reference to a character in the same Solomani stories for which their planet is named. Ostensibly house pets that control native vermin, reep are ubiquitous in Narnian settlements. Every single Narnian has an individual reep as a pet, and this animal is treated with great affection. Natives refuse to be separated from them, and become agitated and angry without them.
This has a biological basis.
Research revealed that 98% of the Narnian population is infected by a native parasitic protozoa, Exoplasma narnia. This lifeform is spread by the reeps and also transmitted by mothers to children. It produces neurological changes in host brains so that they become docile, sensual, and addicted to their pets.
The accidental addiction of several scouts and traders led to the Third Imperium interdicting Narnia to prevent the spread of the parasite. The Solomani Confederation has maintained this interdiction.