Seaweed rice ball, also known as 'Oishii' in Japan, is a popular Japanese dish consisting of vinegared rice wrapped in seaweed leaves. The design of a store for selling this dish would typically focus on creating an inviting and authentic Japanese atmosphere, with elements like sushi bars, display cases showcasing the variety of seaweed rice balls, and a clean, modern layout. The design may also include cultural motifs and a warm color palette to enhance the dining experience.