I got this one and a couple others like it in Tokyo.

Nothing suspicious about it, dark but not fully opaque fluids like soy sauce start out light but get darker as it gets deeper

I got these (and the chopstick holders) as a wedding gift from a friend in Japan, we either used kikoman low sodium or the soy sauce that was included with the sushi

Now clean it.

That is cool as fuck.

Gorgeous as a piece of art, mildly infuriating to be served this in a restaraunt... I want to dip in the sauce and be able to get to it.

This is so neeeat!!

Wow that's a smart design!

I got this one in Tokyo.

Also, I'd recommend tamari instead. I don't think it's as traditional for sushi, but it's less salty and richer. It seems less likely to overpower the fish rather than complement it.

I never realized until now that those shrine structures look a lot like native north american "Inukshuks".