.
Always good to check posts after they have been published,
Ckrazyckid... as you can see, there was a snafu with your attachments.
Not that it matters, because RCT-376
("Lewd Brothers and Sisters in a Sexual Game in Which On a Given Turn Incest May Occur, A Brother Taps a Naked One to See If It's His Sister!") would be a hard one to get the complete cast listing of. The only actresses listed in
Sougouwiki are:
Scene 2:
Erika Kitagawa (北川エリカ, the sister; from HBAD-193)
Nao Katoh (加藤なお, the mother; from MUSK-013)
Scene 3:
Maria (真梨亜 / まりあ)
If
Sougouwiki's information is correct, it is a good thing they have highlighted the women in Scene 2, which is what you are looking for.
(The translated Japanese description and title only speak of brothers and sisters... so I don't know why Nao Katoh above was labeled by
Sougouwiki as a mother.)
Helpful screen
shots 1 and
shots 2.
.