mochi in a fried tofu pouch; mochikinchaku
A common oden ingredient: a piece of mochi (glutinous rice cake) wrapped in a pouch of aburaage (fried tofu) and tied with a strip of kanpyō (dried gourd) or similar. The pouch absorbs the oden broth and becomes soft and juicy.
See also: 巾着 (きんちゃく)
When you put mochikinchaku in oden, it soaks up the broth and becomes delicious.
I often buy mochikinchaku at the convenience store oden corner.