In this segment, they are talking about what they're No.1 at
One of the presenters wrote "Asoko", which literally means "there" and is commonly used to refer to male or female genitals.
However, Miyawaki Sakura mistakenly reads it as "Ariko" (the Japanese syllable "ri" and "so" written in Katakana look similar and is often mistaken) and the adults try to play along with her mistake.