Nanana's Buried Treasure

"I'm going to build a place where young people can challenge to reach any of their dreams!" The 7 genius students, known as the GREAT 7, launched a project to construct an artificial island called Nanae Island to realize their leader, Nanana Ryugajo's peculiar idea. 12 years later, with a total population of 100,000 people with as much as 80% of those inhabitants being students, Nanae Islan...