Kataoka Ken. The same celeb here that's at the party complimenting Anna's mother. This is from a previous chapter when Mama and Anna went on a trip for the shoot.
They are talking about NTR artists.
Because honestly, they kinda are right. You have Anna and Mama here interacting with one of the celebs from a previous chapter who literally got outted for having a black book with young actresses they "had fun" with, not to mention Mama not messaging Papa...