I haven't gone crazy about trying to 100% VNs since Ever17's "you must pick every choice in the game to unlock two bonus artworks" (there are roughly 100 or so irrelevant choice options in Ever17) and the Tsukihime fandisc's insane flowchart that can lock you out of content if you do too much to advance the plot too soon. I'll still 100% a game if there's interesting stuff to be had (No, Thank You!! is a good example) but do you even unlock anything in DR2 other than a trophy? Good luck to you if you still have to scratch that itch.
Well i got the plat for the first game and it was damn fine and easy , i mean in the first game it was getting the normal ending & bad ending, the secret ending , all the characters endings and extra CGS.
It was fine because that was stuff about the game.
BUt dangan 2 went all IN with tamagoshi pets , a action mode with light rpgs elements AND a what if island mode that is not nearly as well made as in the first game. ( the trip ticket balance is BAD )
My save is at 63 hours, 41 minutes and 57 secs.. and i'm still not done..
*Sigh* if only the things missing weren't behind that annoying Random luck drop.
My save for dangan 1 is at 32 hours only. i just can't believe it.
To answer the question .. the game artwork section is filled with concept art, all the music in the game and all the events & CGS , but right now what is annoying me is that this stuff is just some side activity bullsh*t