...this would probably be the answer.
The smart K, sold from 2001 to 2004, it is likely the worst selling kei car ever, and the only gasoline powered kei class car NOT built in Japan (there is a South Korean company called CT&T United that sells Korean built electric cars in the kei class in Japan).
I came across this heading into Aki.
The things that give this away as a K are the narrower wheels and tires, narrower track, and the yellow license plates that are given to cars that slot into the country's dimensional and displacement regulations for kei cars.
Unlike the typical Kei car, which is domestically built, the smart K was built along side the normal ForTwo in their plant in France.
Sales never met expectations, and the model was discontinued in late 2004, though smart does continue to sell cars in Japan, just not meeting Kei regulations like the K did.