Tokio

When he was young, Tokio and his brother met a group of thugs harassing people in Shibuya, they tried to stop the harassment but his brother ended up dead. There is no witnesses because the two who got harassed went missing, and the gang members were still kids, so they got off free. Following the incident, Tokio's mom fell ill and later died.

5 years have passed and now grown-up Tokio returns to Shibuya again to find the one who's responsible for his brother's death.