Yamashita, the main character, had come up with an idea for a new product and was on his way to the patent office to obtain a patent. He had developed a snack food using karinto, which he was convinced would be a huge hit.

At the patent office, Yamashita spent some time going through the paperwork. He ate some of the rinto he had left on his desk while he was working on the paperwork. He then headed to the counter to submit his paperwork.

But by the time Yamashita left the patent office, he could not taste the karinto at all. He was puzzled, and was told by a Patent Office official that the taste might return after crossing the Great Seto Bridge.

Yamashita decided to cross the Seto Ohashi Bridge, half-convinced by the staff member's words. And as he began to cross the Seto-ohashi Bridge, the taste of karinto gradually returned. He was astonished at the strange phenomenon.

After crossing the Seto-ohashi Bridge, Yamashita noticed that the taste of karinto had completely returned. He thought that this phenomenon might lead to the development of a product, so he went back to the patent office and succeeded in obtaining a patent for a new product using karinto.

He then decided to market the phenomenon of the Great Seto Bridge as an attraction for his product. He marketed his product with the catchphrase, "Crossing the Great Seto Bridge makes the karinto taste even better.

As a result, Yamashita's product was an instant hit and became known nationwide. And the strange phenomenon of the taste of karinto returning became widely known as the "Seto-ohashi phenomenon.

Yamashita was delighted to see his idea come to fruition and become a huge success. He was also grateful that so many people had come to cross the Seto-ohashi Bridge to experience the phenomenon.