Kluuda is an Exekian term for a specific event in their reproductive cycle. There is no direct equivalent in any human language, although it is often translated as "puberty", "blood fever", or in a derogatory fashion with terms such as "rutting" and "in heat" depending on the context.
While they can engage in sexual activity at any time, Exekians are only capable of producing offspring once every 214 years, making them technically seasonal breeders. The period of time in which they are fertile is known as kluuda; the term also refers to the bodily processes their species undergoes in order to reproduce. Historically kluuda has always been a foundational component of Exekian society, with the Old Exekian Empire measuring the passage of time in eras which lasted 214 years, marking each new reproductive cycle.
Due to the many wars between humans and Exekians in the mere two centuries since the Revolution, the population of the Exekian species has plummeted drastically, with no new Exekians being born to keep the balance. Thus, despite their immortality, the Exekians are on their way to becoming extinct.
For the first 214 years of their lives, Exekians are not sexually active. Upon reaching their 214th year, however, they experience dramatic changes. The first signs and symptoms of kluuda include a reduction in physical strength and reaction times, along with a feeling of weakness and sluggishness. This is followed by fever, raising their body temperature to abnormal levels that may cause disorientation. In some severe cases, it may even lead to memory loss or loss of awareness. Throughout all of this, the process awakens their sexual drive and stimulates fertility, compelling them to mate.
Due to all Exekian children being born at around the same times, the entire species is affected simultaneously by kluuda regardless of location, age, or ethnicity. While they take steps to regulate the process, kluuda always has a profound destabilizing effect on Exekian society, leading to social tumult and, under the right circumstances, complete chaos. In their weakened state, they are more vulnerable to attack, and the disorientation, amnesia, and loss of awareness associated with the onset of the blood fever can lead to acts of violence and exploitation committed by Exekians against other Exekians.
When the time of kluuda draws near, it is common practice for Exekians to gather up supplies and retreat into their homes with a chosen mate, remaining there for the duration of the kluuda. It is considered safest to limit one's contact with others during the process, both to avoid potentially dangerous conflicts and to satisfy one's urges in a controlled scenario without disruptions.
While Exekians did not usually practice marriage, a short term union or binding contract might be devised for this purpose. Under the Exekian Empire, it was also considered acceptable (if humiliating and/or disgusting) to copulate with a human slave during kluuda if one had no other choice. This was also looked down upon as wasteful and pointless, as no offspring could result from engaging in sex with a human.