The bug affects everyone.
Under Edwarda, tier 2, sometimes you get hits for Athena, sometimes for Naisha.
Only way to know how much hits I got on Naisha is clicking the hit while it is on screen, I know I am around 20/100 right now.
Then you go in Harem, Naisha is not listed at all under Harem, I browse the whole list, try finding a girl with a straw hat... simply not listed.
I hope when I get 100/100 that I will get her in my harem, but if invisible, I won't be able to collect her.
Good chance she will become visible when I get her, or event girls from past events won't show if that was the case...