A donuki is an under-kimono worn on top of the nagajuban, but under the outer kimono. It has two different fabrics, one for the body and a fancier fabric on the areas that can be seen when wearing the top kimono. (The wrist and sleeve openings, collar, and bottom hem) Donuki add formality to an outfit, and as such they usually come in sets, with the outer kimono and the donuki matching/complimenting each other, but sometimes they show up separated from each other or by themselves. (As is the case with the one I won on eBay this weekend, shown above)
This is my first Donuki, and while it does not have a matching top kimono, I still plan on using it to add a sense of style to an outfit. I’m not sure what motifs are on it though; I haven’t received it in the mail yet, so I can only go by what I can see in the seller’s photos. The one close-up photo is of a strange plant/berry that I have never seen. The ladies on IG have tentatively identified it as nandina, more commonly known as “heavenly bamboo” or “sacred bamboo”. I can also see mum and what might be maple leaves in some of the patterns. I’m not sure what season nandina falls under, but this donuki does seem to be rather autumn-y to me.
Even if you do not own a donuki of your own, it is relatively easy to “fake” the look of one by using a date-eri sewn or clipped to the edge of the kimono collar, making it seem as if you are wearing two kimono or a donuki/kimono set. This is quite common when wearing furisode in fact, since a date-eri adds the formality of a donuki set without the added weight or hassle of wearing two kimono on top of juban and hadajuban.