"Riku is a central character in the Japanese manga series ""Today to Tomorrow"". He plays a crucial role in the plotline and his actions have a considerable impact on the storyline's direction.

Riku is a high school student, and his appearance matches his age. He has short brown hair and a lean body. He stands out for his confident and matured demeanor, which a lot of people find attractive.

Riku is also a gifted athlete, often playing basketball and other sports during his free time. He takes his sports seriously, and his training routine is strict, which reflects his dedication and ambition. As a result, he is well-known among his peers and has lots of admirers.

However, Riku hides a dark secret. He relies on drugs to enhance his athletic performance, and many of his achievements are due to his reliance on these substances. His fear of losing his competitive edge leads him to consume large quantities of these drugs, which eventually affects his mental and physical health.

Despite his success, Riku longs for something more meaningful in his life. He wants to find a purpose that goes beyond sports and recognition. He is introspective and thoughtful, always striving to understand the world around him better.

As the story progresses, Riku's struggles with drug addiction and his search for meaning are explored in depth. He becomes a critical character in the story, whose actions drive the plot forward.

In conclusion, Riku is a complex character with numerous facets that make him both fascinating and tragic. His struggles with addiction and his search for a higher purpose make him an essential part of ""Today to Tomorrow"" and a captivating character in his own right."