Allow Geils to kill you to view an alternate ending.
Blood type and vampires
Selecting a blood type (A, B, O, or AB) at the start of the game will have an effect on the type and difficulty of the vampires that will be encounted during the game.
Hidden Graphics
Enter the name Yuka Kobayashi. Now get to a computer at the second or later save point.
Play as Vampire Keith
Enter the name Prince Darkness.
Special mode
Successfully complete the game in under seven hours to unlock special mode.
Alternate ending sequence...