The moment the entire group forgives Seth, join hands, and banishes the darkness from Cheshunt forever. Till death do us part, indeed.
In particular, there's Nissa, who cries for the first time in the entire story, signifying she has let go of the anger that she uses to protect herself from pain.
The group hugging after rescuing Seth from his attempt at killing himself is equal parts this and Tear Jerker.
Danny's description of how he met Lallie after being attacked by the Gathering; her wiping the blood from his face and convincing him that to make justice happen, he needs to believe in it.
Nathaniel's description of Mrs Bunnie, the English teacher as she reads out Shakespeare "In the voice of someone younger, taller, and more beautiful."
The Tod. Just... everything the Tod does is simply adorable. Particularly getting his face covered in sand at the beach and boldly charging against a pack of feral dogs five times his size to protect Nathaniel, and being hugged for his trouble.
There's a Tear Jerker to this though as Lallie bringing the Tod to him it counts as interfering with the proceedings more than she is permitted, which means Karmic Backlash kicks up and results in the Tod's death.
There's something nice about Mr Pelman, who basically adopts Nathaniel whenever he visits his mother's workplace, and worries a lot about "him not having a girlfriend yet."
It's funny how, after being the one most suspicious of him in the beginning, Danny ends up becoming quite protective of Nathaniel. Nathaniel is the first person he has ever told the whole story to of being attacked by the police and their dog. He had never told anyone that story, but he told Nathaniel, because he needed to understand that people aren't good just because they look like good guys to society.
I opened my mouth, not sure what I wanted to say, That I was glad he had told me what had happened to him. That it made me sick and angry. That he had more guts than anyone I had ever known.
'You're alright too, Danny-O,' I said at last.
There's an added layer, as Nissa had earlier used the nickname 'Danny-O' more harshly, signalling what she thinks of Danny's willingness to get rid of anyone who might risk exposing the chain. That Nathaniel uses it now, when it was originally used in a context where Danny was willing to kill him , speaks volumes.
Nathaniel's moment with his mother at the Zoo. With their usual relationship being so tumultuous, it's nice to see this calm, happy occasion of an awkward mother and son just having a day out together, and at least trying to work things out.