You'll need the wayback machine. A man stands in front of a door. It can lead anywhere. Dare you step through? -- Anon Guest
Presented for your approval, the image of a man in a grey suit. The man is also in tones of grey. To see him, and the door he offers you, is to see into different realities where anything from creeping horror to sublime delight awaits on the other side. It is, without a doubt, the trip of a lifetime. If you survive, it will be a life-altering experience.'
If you don't survive... well... people disappear all the time, don't they? The missing, the absent, the lost... those who are there one minute and gone the next. The shadows in the corner of your vision. The sensation of being followed, only to find no-one there. Those are the ones who failed to learn the lessons in the twilight lands, and are doomed to educate the others.
There's no name for the realm into which the grey door leads. Not one that can be spoken without sheer tonnage of cultural load crushing the reader with its impact. Call it what you please. The twilight realms, the kharma zone, the faewraith... what matters is that those who enter it are luckier than you may believe. Those who survive to come back are forever changed. Whether or not it is for the better is not for us to judge. The judges, after all, have already done their work.