Probably the last chibis I'll do.
Anyway Takahashi pissed me off with these two. For one she NEVER showed us what Koga's real form looked like (not even a concept sketch) and another was she said she liked Ayame and wanted to add her to the manga, but ultimately never did.
I mean I understand it would have been hard, what with trying to come up with a way to put her in there without making the plot line seem awkward, but the least she could have done was "Hey um...turns out I can't find I way to get her in there. Sorry. Don't hold your breath".
At least Ayame turns up in Inuyasha: Final Cut. There's a spoiler to that but you can go find out on your own. Especially since Hulu has all episodes, nice quality, subtitled, and free. Granted there are commercials to sit through, but hey it's free, so grin and bear it.