March 1897 cover, Japan to St. Paul, MN USA

This arrived in the mail yesterday from a seller in Nebraska. It is interesting to me because of the notation at upper left, "To. San Francisco Cal. Per S/S Coptic."
I have a 1 yen, old die, JSCA 157, with an RCD-1 port postmark, Persia Maru. I have also included that image for reference as my cover image for this collection.
The Coptic was the original christened name of the Persia Maru when it was built in 1881. In 1897 she was chartered to the Occidental and Oriental Steamship Co. and served between San Francisco, California and the Far East.
This cover was postmarked in March of 1897 but later that year, in September, she collided with the Minatogawa Maru in Kobe harbor.
The cover has 2 copies of the 5 sen Sino-Japanese War commemorative depicting Prince Arisugawa Taruhito. Despite being very faint, I believe the double postmark strike is Kobe. There is a a letter "E" that is recognizable in the lower of the two strikes underneath the stamp closest to the edge of the cover on the right.
On this side of the cover, I wonder what the following means, "c/o Japanese stor?" at lower left. I am unsure if this is a correct reading of this word. I welcome any help. Is this the word, "store"?
On the reverse there are additional postmarks of Yokohama on Mar 6, 1897, a receiving postmark in San Francisco on Mar 21, 1897 and finally, Saint Paul, Minnesota on Mar 25, 1897.
There is also a red oval marking with YSKW in the lower part of the oval. Does anyone know what this is? My assumption is that it is a business and possibly having to do with the silk trade. Again, any help would be appreciated.
A little bit more difficult but perhaps not impossible to determine, is who, T. Naka, Esquire, is and what was he doing in St. Paul in 1897. In modern times, according to Google Maps, there is no longer a building or home with the address of 377 Wabasha in St. Paul.