Book 5, (book 6 chronologically because Martha Wells decided to make things difficult)
but people want to pretend like Murderbot's actually getting more comfortable with letting people touch it, rather than getting more comfortable setting firm boundaries. Because they don't like the message the author is beating them over the head with.
Arada rubbed her eyes and her mouth pulled in at one side. “Are you trying to make me feel better?”
“No.” I actually wasn’t. I lie to humans a lot, but not to Arada, not about this. “I wouldn’t try to make you feel better. You know what I’m like.”
She made a snorting noise, an involuntary expression of amusement. “I do know what you’re like.”
Her expression had turned all melty and sentimental. “No hugging,” I warned her. It was in our contract. “Do you need emotional support? Do you want me to call someone?”
“I’m fine.” She smiled.
This is character development for everyone involved (Arada took the longest to figure out Murderbot didn't want to be touched because she wasn't picking up on its nonverbal cues the way Mensah did, Murderbot has been learning to TELL people it doesn't want to be touched rather than just bearing it in silence), but because solitaremisics don't like the fact that Murderbot is reaffirming and strengthening its boundaries instead of weakening and compromising on them, they pretend like this isn't what's actually happening.
Even though it's a very clear linear progression from book 1 to this point that is not at all difficult to understand as long as you aren't already determined to pretend it's not happening.