Drahvin

Drahvins were a female-dominated humanoid race.

Biology
The Drahvins were physically similar to humans, but blond and generally attractive. (DWN: Galaxy Four)

Culture
The Drahvins had a rigid caste system. On top were the Elite, with the scientists, leaders and military commanders. They could be identified by their scarlet clothing. They were allowed actual food, could vote and had a normal birth. Below the Elite were the slave class, which did menial labour. They were artificially created and were given limited intelligence and creativity. They would be given a number instead of a name (such as "Drahvin One"), were fed on food pills and were expected to obey the Elite without question. Males had no part in this system and only a small number of males were kept alive for reproduction, the rest being killed to preserve resources.

Drahvin government was split up into Ministries, such as the Ministry for Offensive Research. Though the Elite had a vote, their was only one political party and little actual change. (DWN: Galaxy Four)

Drahvins do not understand the concept of giving one's life for an individual. Failure is considered inexcusable and it is standard policy among the military Drahvins to shoot the wounded. (DW: Galaxy 4)

Technology
The Drahvins had somewhat limited technology. For example, their ships were made of common metals, making them functional but not particularly durable. They used guns physically similar to the machine guns of Earth, but which used energy instead of bullets. In an attempt to stop the Chumblies, they also used a mesh-net which could incapacitate them. (DWN: Galaxy Four)

History
At some point in their history, the Drahvin homeworld, Drahva, was cooling down, killing the vegetation and forcing the Drahvin to find new planets to colonise. One ship, led by Maaga and with four Drahvin slaves, encountered a Rill ship. The Drahvins attacked, but were defeated, causing them to crash onto an uninhabited planet. The planet was doomed to destruction and though the Rills wanted to work together with the Drahvins to escape, the Drahvins attempted to take the Rill ship by force. When the First Doctor, Steven and Vicki came to the planet, Maaga tried to trick, then force the Doctor into helping them destroy the Rills and escape the planet, but failed. The Drahvins died when the planet exploded. (DW: Galaxy 4)

In 102, the Drahvin were among the races who joined the Alliance. They came to Stonehenge and helped imprison the Eleventh Doctor in the Pandorica in order to save the Universe. (DW: The Pandorica Opens)

The Drahvins attempted to invade Earth some time prior to 1997. UNIT fought them off without the Doctor's assistance. (NA: The Dying Days)

The Drahvins had competitors in the 309th Intergalactic Song Contest. (BFA: Bang-Bang-A-Boom!)

Behind the Scenes
Lance Parkin has stated that the Drahvin invasion reference was a joke, based on the Drahvins being "rubbish" monsters, and that "some alien invasions were beneath the Doctor’s dignity to deal with".