Core Path Lab Nex
Our products

Worn Close. Made to Last.

Core Path Lab Nex is a Tokyo-based boutique offering swimwear and lingerie cut from European lace, Japanese cotton voile, and hand-dyed silk. Each piece made in small runs of twelve.

I carried that bolt of lace back from Normandy in my carry-on luggage.

The Current Collection

Calais Bralette in Sand Cut from Calais lace in a warm sand tone, dyed by Irodori-ya in… ¥18,400
Riviera Bikini Top in Blush A triangle top cut from Italian deadstock silk in a pale blush,…
Riviera Bikini Bottom in Blush Matching brief-cut bottom in the same Italian deadstock silk ch… ¥14,200

Oggi dal forno

New stock photographed and listed online 09:00
Thursday/Friday fitting appointments begin 11:00
Made-to-measure orders cut and assembled 14:00
Daily dispatch packed and collected by Yamato 16:00
Our products

What We Stand For

Small Runs Only

Every style is produced in runs of twelve. When a size sells out, it does not come back in that colourway. This keeps the work considered and the wardrobe rare.

European Lace, Japanese Hands

We source Calais lace from a mill in northern France that has been weaving since 1898, then finish each piece in our Nakameguro studio with local seamstresses.

No Underwire by Default

Our bralettes and bikini tops are structured through cut and fabric tension, not wire. Comfort is not a compromise here. It is the starting point.

Natural Dyes Where Possible

Our blush and sand tones come from plant-based dyes developed with a small dye house in Kyoto. The colour shifts slightly with each batch, which we consider a feature.

News & Announcements

News & Announcements

2026-03-15

Calais Lace: What Makes It Worth the Price

Most lace sold in lingerie today is raschel lace, made on a warp-knitting machine that can produce metres of fabric per minute. Calais lace is made on a different machine entirely, a Leavers loom, and the process is slower by an order of magnitude. The difference shows up in how the fabric moves, how it ages, and how it feels against the skin.

Read more →
2026-04-22

Plant-Dyed Lingerie: How the Colour Gets Into the Fabric

Natural dyeing is not a new idea. It is, in fact, the only kind of dyeing that existed until the mid-19th century, when synthetic aniline dyes made colour cheap and consistent. The consistency was the point. Natural dyes are not consistent, and that is both their limitation and, for certain purposes, their appeal.

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2026-06-01

How to Choose Swimwear by Body Proportion, Not by Size

Swimwear sizing is notoriously inconsistent across brands, and the standard S/M/L system tells you almost nothing useful about whether a specific cut will fit your body. A better approach is to think in terms of proportion: the relationship between your bust, waist, and hip measurements, and the specific cut of the garment you are considering.

Read more →
With respect

From Our Customers

I wore the Riviera set to a resort in Okinawa last August and received more compliments than I have ever received on a swimsuit. The silk holds its shape even after a full day in the water.

Yuki M. · Tokyo

The made-to-measure bralette fits in a way that nothing off the rack ever has. Emiko's fit notes were clear and the four-week wait was completely worth it.

Claire B. · Paris, ordered online
4
Weeks lead time for made-to-measure
12
Pieces per colourway run
3
Fabric suppliers, all long-term
Who

About the work and the worker

Founder, Established since 2019

Emiko Harashima

Emiko Harashima trained as a pattern cutter in Tokyo, spending six years at a Shibuya-based ready-to-wear label before founding Core Path Lab Nex in 2019. A trip to Normandy in the winter of 2018 introduced her to the Calais lace mills that now supply the studio, and she returned with a bolt of fabric and a clear idea of what she wanted to make. She bakes bread on Sunday mornings, keeps a small collection of vintage French lingerie catalogues, and believes that a well-cut bralette should feel like wearing nothing at all.

Emiko Harashima
FAQ

Common questions

Q.How do I know which size to order?

Each product page includes fit notes written by the seamstress who made that specific garment. We also have a size guide with body measurements rather than generic S/M/L labels. If you are between sizes or unsure, email us at us and we will help you choose before you order.

Q.Can I return or exchange a piece?

We accept exchanges on unworn, unaltered pieces within 14 days of delivery. Because our runs are small, we cannot always offer a direct swap, but we will find a solution. Made-to-measure pieces are not returnable, as they are cut to your measurements. Swimwear is exchangeable only if the hygiene seal is intact.

Q.How does the made-to-measure service work?

You download our measurement guide, take six measurements at home (or ask a friend), and send them to us by email. We confirm the fabric and style, you approve, and we begin cutting. Lead time is four weeks from approval. The price starts at ¥38,000 depending on the style and fabric.

GDPR compliant
Your data is yours, always.
Hand-finished
Every piece touched by a maker.
Recycled materials
Reclaimed where possible.
Independent business
Owned and run by humans.
Member of guild
Recognised by trade association.
Get in touch

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