'The Black Page' was a website formerly created by Reiko Asagiri, who's screen name is Kuroneko. Rumors of being able to 'talk to the dead' lead people to the site. There, they find a chatroom. People can chat all they want there. They usually come to talk about the rumors they've heard, or to gossip with each other and discuss if it really works or not. Anonymous, being Makoto, joins the chat. Mie is Chiyo, Mako is Shin, and of course, Rin is Rin. After a bit of chatting, they all get phone calls at the exact same time. Supposedly, if you were to go The Black Page and chat, you would get a phone call. If you were to answer, nothing would be said. You would just fall into a coma and be sent to the Mnemonic Abyss. The Black Page is not assumed to be real outside of the game. Try as you might, you will not find it. You can find chats saying it's The Black Page, but they're not said to be real. You will not be taken to the Mnemonic Abyss if you do chat.
Or will you?