Drella
The Drella of the planet Alpha Carinae V was a lifeform that derived nourishment from the emotion of love.

In 2267, Spock asked the 's main computer whether Redjac, a non-corporeal predator that fed on fear, could exist, and whether there was a precedent for it in the Milky Way Galaxy. The computer mentioned the Drella as an example of an individual that fed on an emotion. ()

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Species
Non-corporeal species