I was trying to read the kill la kill guidebook and started with Inumuta’s passage, and noticed the last sentence mentions Iori.

It says, 伊織糸郎とはツーカーの仲

“ツーカーの仲” is an expression for a relationship that’s so close they know what the other person is thinking

So in Houka’s main description, in the official kill la kill guide book, meant to be an overall summary of his character, they mention his relationship with Iori and just Iori. A relationship that’s so close they know. What the other person is thinking.

ShiHou is Strong and Real