Even if one experiences it and is able to tell it the situation may be too traumatic for them to remember though, it's not unheard of that people will forget things they have gone through due trauma.

No, not Japan or anywhere close to it even. Believe it or not this is another world, you've been taken here, like everyone else who's in this place, from your world. By whom or what, we don't know, but the ones who brought you to this precise place are known as the Malnosso.