An original character by leedoppo, and the subject of many of their 3D animation works.
As depicted in her reference sheet (post #6122122), she is a Jeet Kune Do practitioner who has grey hair styled in quad tails, held up by twin yin yang hair ornaments. Her eyes are yellow and lined by a small crescent of red eyeliner. She wears a dark blue tangzhuang jacket with red frog buttons and a stylised yin yang symbol on the back, and a white shirt underneath. She wears matching dark blue shorts and black yoga pants adorned with dragon print, and white footwear.
Note: Certain lighting conditions and fanart interpretations may make Ruru's tangzhuang and shorts appear black, dark grey, or even dark green.