A student handed a blank sheet but a detail earned him the highest grade

The Japanese student Eimi Haga delivered a completely blank sheet in the review of the ninja history course he was performing at the University of Mie, Japan. The surprise? He had the best rating.

The thing is in the ink. The young woman took advantage of the fact that the teacher had asked them to write about a visit to Ninja museum in Igaryu. The 19-year-old girl used a technique encountered at this location: soy ink, invisible, which does not appear commonly on paper.

As if she were a spy, she wrote everything and left a note with normal ink, who tells the teacher to "heat the paper" to prevent it from resetting it.

When the teacher placed the sheet on a gas stove, the letters appeared.

Eimi found on the Internet how to make this special ink and followed the steps in detail. He bought soybeans, soaked them in water and crushed them. Then he pressed the crushed seeds, mixed the extract with water and finally applied the result on a brush that he applied on three types of paper "washi", very fine in Japan.

The result, in addition to giving him a worldwide fame, earned him a 10. The teacher also praised his creativity. "If I have the opportunity, I want to write an essay using another ninja technique," said the young woman The Asahi Shimbun.