This was just a chance encounter, and because it was a chance encounter, it was quickly forgotten.
It was just a chance encounter, and there was no trace of it in the vast memory.
However, if you suddenly think of it, there is nothing wrong with it. Perhaps the god who arranged that encounter was unwilling to let his careful design be forgotten. Kagome Higurashi, who was already the mother of two little half-demon, had a dream.
The scene in the dream was something that actually happened to Naraku more than ten years ago when she was still alive.