Kei (or Braslota III) was the third planet in the Braslota system. In 2365, this planet was chosen as an element in Operation Lovely Angel, a Starfleet battle simulation.

In the exercise, the starships USS Hathaway and USS Enterprise-D were to attempt to defend against an simulated assault on the first planet, Totoro, from forces originating from Kei, while maintaining control of orbital space of the second planet, Yuri. (TNG: "Peak Performance")