Musubi mean making a knot. They are also packages of rice, to take with you as lunch pack. The plastic film gives the shape to the ball.
A mix of genmai (brown rice), mochigome (sticky rice), kurogome (black rice, sticky too) and takakibi (sorghum).
Pickled sakura leaves, rinsed.
Wrap. Keep a few hours, or better the next day. The leaves are not very tasty but give a sakura flavors and saltiness to the rice.