I don’t like to use the word “grooming” because I think his plan was only to get with Charlotte, or at least live vicariously through her family. His friendship with Penny may not have been appropriate (though I think intergenerational friendships can be healthy) but I don’t think he ever had sexual intentions or even expected to genuinely gain her trust. He just liked that someone didn’t expect him to act like an adult, without realizing that Penny did see him as an adult and liked the lack of boundaries he set because it made her feel more powerful. So it’s the sort of mentality a groomer does exploit, but I don’t think BoJack was self-aware enough to consciously groom her. A middle-aged man and a teenage girl can be friends and it’s not grooming if the teen girl develops a crush on him because she’s naive and desperate and trusts anybody who is nice to her. The issue is whether the man is responsible enough to set boundaries.

But obviously that doesn’t make what he did any better. He did eventually acknowledge the similarity between Penny and Charlotte, and it’s telling that he only left the door open after Charlotte rejected him. He lost his actual goal so he decided to throw caution to the wind and just do something shitty that would either A) burn bridges with Charlotte’s family so he didn’t feel tempted to come back or B) make him feel like he’s young again. People forget the “age of stagnation” quote from earlier this season – BoJack thinks he’s still young, he wanted to project young and immature Charlotte onto Penny because Charlotte matured and BoJack did not. He was very passive about it but he clearly wanted to give Penny the option so he could go numb and do nothing and convince himself it was her mistake. Despite the fact he’s the one old enough to know what he’s doing is wrong.

It’s predatory either way whether we use the term “grooming” or not.