Neisan's early history is currently unknown.
In Spirituality, Neisan is among the two students that remained behind to witness the others fighting Aroti. During the fight, he simply stands off out of the way. After the fight, he ends up being sucked into Kodi along with almost everyone else.
After meeting Eiden, and exchanging words, Neisan plummets down a trapdoor with the others, landing in the Abandoned Dungeon. After making it to the otherside of the door, Neisan and everyone else obtain swords. Neisan's sword's name was, Sereti.
At the school section, they meet Kodi , who was at the time being controlled, and battled him until what was controlling him left. Then, Neisan walked up the Stairs of Infinity with the others.
After making it up the stairs, Neisan rests with the others for a bit, before continueing on. When they go into the next room, the Abandoned Hospital, they discover the presumed dead Desolatus .
After waking up Desolatus and fighting him, Burukku slays the darkling, causing the ceiling to collapse, and forcing Neisan and the others to run through the exit.
After returning to the floor level of Mentality, he and the others go and confront Eiden. After a long battle, they defeat Eiden and move on to the next room, where they obtain armor. Neisan's armor was named, Obadoraibu.
Shortly after this, they encounter and battle the Dight. Then, Neisan and the others enter the C.P.U. Base, and then into a gray room, where Makura is suspended above them, wrapped in chains.
After receiving a book and an explanation from Makura, they leave and go to Nishrung, where Sebasuchan is waiting. After a long, strenuous, and perilous battle. Neisan and the others defeat Sebasuchan, and are teleported out.
Neisan wakes up in his bed, and after going to school, he finds out about Kodi's new condition.
Neisan is portrayed to be very curious and is prone to ask questions. He is brave and independent.