The long and short of it is that Haseo develops feelings for the enigmatic guild leader of the twilight Brigade, Shino (who, critically, looks almost exactly like recolored atoli) At some point, Ovan vanished, Shino was player killed by the "player" (obviously some sort of AI, though haseo doesn't know that) known as Tri-Edge (pictured below), which put her in a coma in real and the guild fell apart. Haseo completed a bugged quest that power leveled him to level 133 and, in a frustrated rage he becomes a famous player killer killer, trying to find tri edge.
The game opens with Ovan, coming back out of nowhere and telling Haseo that Tri-Edge will show up where he killed shino again. Haseo fights try edge, but also gets killed, but instead of going into a coma finds his level has been reduced to 1, which is how the game proper starts