The bottles (ceramics and porcelain) are used for Sake container (especially hot Sake).
The shape is with it narrow neck and swelled bottom. And the materials are of ceramic, metal or glass.
The ceramic is the most popular to keep the nice taste from a bad influence of the materials.
And owing to the narrow neck, we get a nice sound Toku-Toku-Tokun pouring forth out.
This tiny gurgle makes any drinker mad. We can stand it.
As a traditional Japanese bottle, it has been getting important part in our daily life since our ancient time. In fact comic storytelling (a vaudeville performance in japan) "Rakugo" told us "the scene of pouring Sake has appeared on many times".
Have a drink "Japanese Sake" with these nice bottles and taste it as if a cool drinker.
Now you are just like a Japan watcher.