D is a horror adventure released by Warp for 3DO in 1995. Due to its huge success in japan, the game was ported over to Sega Saturn, Sony PlayStation and PC.
Later that year, a special edition was released as D's Diner Director's Cut for 3DO that features trailers for the game, a "sound novel" that tells the history of Laura's family and the soundtrack of the game on MiniDisc. The game itself had several new scenes added to this Director's Cut edition. But unfortunately it was only released in japan.
This longplay features the game with the best ending. To get this ending, you have to kill your father, and find all four scarab beetles during the game. You're then rewarded with a crying baby, and a trailer for the never released sequel D2 for Panasonic 3DO M2.
I also added the bad ending to the end of this video.