Shinjuku Golden Gai — the town that never sleeps.
In a quiet corner of this lively neighborhood stands a tiny shop with no signboard.
That is OPEN BOOK.

Founded in 2015 with the slogan “The world’s best lemon sour,”
the shop’s signature drink is a refined blend: brown sugar shochu, syrup made from domestically grown pesticide-free limes, sliced lemons from Hiroshima, served in a thin glass with large ice cubes.
A drink full of Japaneseness and elegance, it remains our unwavering signature.

The shelves are lined with books inherited from the owner’s grandfather, the late Kojimasa Tanaka.
It’s a space where literature, sake, and transnational culture converge.
Countless people and stories have connected here.

The lemon sour, nurtured by the city of Shinjuku, has become more than just a drink.
Why do we say this lemon sour connects everything?
The answer lies in this city — and in this glass.

And the connection keeps growing.
From a small corner of Shinjuku, to Japan, and beyond —
we're expanding into liqueurs and canned products.
One sip, and everyone opens up.
Like turning a page, new encounters and stories begin.
Drink, and you’ll understand.When we connect, everything becomes more interesting.

OPEN BOOK will continue to be that kind of place.