Kirill Vrubel is one of the main protagonists in the anime series 'Double Decker! Doug & Kirill.' He works as a rookie detective in the special investigation unit called Seven-O, where he partners with the seasoned detective Doug Billingham. Despite his initial lack of experience and somewhat naive demeanor, Kirill is determined and enthusiastic, often bringing a fresh perspective to their cases. As the series progresses, he showcases significant growth, both in his detective skills and as a person. His quirky personality often adds a comedic touch to the show, balancing the more serious tones of their investigations.