It had been 2 months since the fateful occurrence between Inuyasha and Kagome. That night when they both confessed they're love for each other the world took a twist. For that night she and Inuyasha had made love, and since this was during the new moon Inuyasha was a human, Kagome often wondered if their unborn child would be a human, or a quarter demon.
The rest of the group didn't notice the change right away but it was noticeable. For instance Inuyasha started to make Kagome sit out of most of the fights, started to make sure they stopped at least twice a day so that Kagome didn't wear herself out.