You're one of the survivors of the invasion of the mysterious parasite "Obscura". You had a mission to find other people who are still alive. On the previous trip, you found a radio tape. You put the radio tape into the tape player.

We don't know what they are... We don't know what they want... Sometimes... They could be watching us from certain places... They are alien parasites... So... Stay on guard... Or your body will be taken over by them...