Sui Gin may be poor, but he is one of the best online video game players. This identity however, is unknown to all except for RikuLei, Sui Gin's classmate. She delivers a mysterious mobile device to Sui Gin but before being able to explain herself, RikuLei is kidnapped and Sui Gin unwittingly finds himself wrapped up in series of problematic circumstances. Searching for a way to save her, he accidentally activates the device allowing him to dive into a new Virtual game-world.

[Source: Anime News Network]

Secretly in love with Riku Rei, the most popular girl of his school, Riku Suigin is forced to dive in “Grave Buster”, the new virtual game where Riku Rei has been kidnapped.

To save her, he will have the support of the beautiful Twin Star and in addition to that he has inherited a 10 billion of yen charged device by his grandfather Ruki Yuuki.

Suigin will have to become the last Guardian who protects the Tomb from the Raiders in order to save Riku Rei and solve the mysteries of Grave Buster.

[Source: Crunchyroll]