The Buyer
Sei Hasegawa —
your man in Tokyo
Background
Sei Hasegawa is a Tokyo-based expert in Japanese designer archives, with over a decade of experience identifying, authenticating, and sourcing garments from Japan's secondary market. His focus is the radical output of the 1990s and early 2000s — the era when Comme des Garçons, Yohji Yamamoto, and Issey Miyake were redefining what clothing could mean.
Growing up in Japan during the peak of this movement gave Sei an intimate relationship with the garments themselves: their construction logic, their label histories, their seasonal codes. That knowledge is not something that can be taught from a catalogue — it is accumulated through years of market immersion.
What Sei does
Sei sources personally from Japan's secondary market on behalf of a small number of trusted international boutiques. Every piece is assessed in person at Sunmaloo's Chigasaki office: condition, authenticity, and coherence with each partner store's aesthetic.
Rather than sending a static inventory list, Sei builds a curated monthly selection tailored to each partner's profile. The goal is to become a trusted extension of your buying team — someone in Tokyo who already knows your store's voice.
Career
Present
Co-founded Sunmaloo Inc. to formalise international B2B wholesale of Japanese designer archives. Oversees all sourcing, authentication, and client relationships.
2022
Sourced and brokered archive pieces privately for collectors and boutiques across Europe and Asia. Built deep knowledge of Japan's secondary market infrastructure.
2016
Worked as an in-store buyer for a specialist vintage retailer in Tokyo, developing authentication skills and supplier networks across Japan's used-clothing market.