Tamura Yukari, a voice actress and a singer, famous for roles like Ten Ten of NARUTO, Takamachi Nanoha in Magical Girl Lyrical Nanoha, and Natsukawa Masuzu in Oreshura, turned 17 years and 7305 days old! The citizens of the "Yukarin Kingdom" are having a national celebration at Pacifico Yokohama in Japan on their national holiday (translation: Tamura Yukari had a live event on her birthday and her fans gathered at Pacifico Yokohama in Japan).
One example of a citizen celebrating it. Aoi Nishimata, a visual novel character designer and illustrator.
Another example of a loyal citizen.
Her birthday live is titled "17 sai dayo! Yukari chan matsuri! (17 years old! Yukari chan festival!)". The fact that she turns 17 every year is an undisputed fact among her fans. The happiness level of citizens of Yukarin Kingdon is also said to be extremely high. For example, even when they are waiting for the live merchandise purchasing line yesterday Japan time, someone showed up with a rice cooker and people just happily tweeted about it, laughing. The rumor turned into a rice cooker being one of the merchandise available. Click here for actual merchandise available.
For those who are not familiar with Tamura Yukari phenomenon, Yukari is forever 17 years old just as Inoue Kikuko is and she is also a royal princess of her own Yukarin Kingdom. The citizens of the kingdom (who would have been called "fans" in any other situation) are known for their military-like loyalty towards their princess and gentlemen / lady like manner.
Here is a video from Yukari live to show how her citizens are well-trained, especially around 2:40. As you see, the citizens are not just audience but the collaborators and the participants of the live show. This song "Chelsea Girl" is considered an immigration check to enter the kingdom.
Click here for more videos if you are interetsed.