I finished it last year. My game clocked somewhere around 80+ hours too but in actual time I think it's almost double. If you have the patience and a little help from walkthroughs this game can make you feel so satisfied when you finally beat it.
There is still some continuation after you beat the game (MILD SPOILER ALERT):
Three months later, you return to the game where it's still under trial period so you can only access Amaterasu Server and even that you can only go to certain areas only. Four new Server Leaders have been established and Kurt is the new MAGAMI President and World Champion.
But... you have to collect all 4 (if I'm not mistaken) epic items in order to battle the Server Leaders which NO ONE is this world has ever succeeded. Only one of the items is able to be found. It's either a glitch or purposely made impossible to do so. At that time I just had to accept the fact that the game's over