Annoyed cat is a lot of Finch's mannerisms. I particularly like that his approach to showing affection towards quite a few people comes across as 'persistently tolerating'. He's not the demonstrative type.

One of the biggest underlying themes to the show is what we can hide and what we can show. I love how the story plays with that in part by having such closed-off characters, all of them wary and hesitant and carrying layers of past around them in a cloud.