What is the biggest clothing company in Japan?

Can you tell me more about the largest clothing company in Japan? I'm particularly interested in their market share, their most popular product lines, and any notable milestones or achievements they've had in recent years. I'm also curious about their approach to sustainability and how they're incorporating eco-friendly practices into their business model. Additionally, I'd like to know if they have any plans for expansion or diversification in the future. Could you provide some insight into these aspects of the company?