Koji Okamoto

Koji Okamoto is a Japanese fashion designer born in 1978 in Hyogo Prefecture. He graduated from Marronnier College of Fashion Design in 2000 after specialising in haute couture and joined ABAHOUSE INTERNATIONAL the same year. His early professional development took place inside the 5351 POUR LES HOMMES studio, where he worked through the Kazuhisa Komura period before assuming principal design responsibility himself.

Okamoto became Chief Designer of 5351 in 2008. By 2010 he was firmly established in the role. His promotion continued ABAHOUSE's internal succession model: a designer already embedded in the brand inherited the chief role instead of an external creative director being brought in to reset the label.

During this phase, 5351 retained its fitted, dark menswear identity and continued to connect fashion with music-led culture. The 2010 Rock'n'Roll Circus project with musician Takeshi Nakatsuka is one of the clearest surviving contemporary credits naming Okamoto directly as Chief Designer and places his authorship inside the brand's established rock-oriented world.

Okamoto left ABAHOUSE in 2012 and became independent, establishing his own design company. His later BLACK LINE activity belongs to that independent career; although he had developed BLACK LINE while still at the company, the exact corporate boundary of the earlier subline is not sufficiently clear to treat its post-2012 continuation as part of 5351.

Okamoto entered 5351 through a long internal apprenticeship, so his chief-designer period developed the existing vocabulary instead of replacing it. His haute-couture training added technical discipline to a brand already associated with narrow silhouette, dark colour and processed material.

The strength of his tenure lies in continuity under pressure. He inherited a commercially established label with recognisable leather and tailoring codes and maintained those codes while working inside a broader corporate merchandise system. The result was evolutionary design instead of a visible rupture between creative directors.

Music and subcultural image remained useful framing devices. Projects such as Rock'n'Roll Circus aligned the clothing with performance and sound, supporting 5351's long-standing idea of adult menswear sharpened by rock attitude.

His 2012 move into independent practice also separated his personal authorship from 5351. BLACK LINE and subsequent work belong to a design career that grew out of the ABAHOUSE studio but no longer represented the 5351 brand after his departure.