Jack giving Harry a platonic hug after the 3rd task and he realises that Harry was essentially mind raped by Voldemort.
The Torchwood team sharing the happy thoughts they use to create their Patronuses, ranging from Tosh creating an artificial intelligence program as a teenager that called her 'Mommy' and Jack recalling how the Doctor and Rose saved his life (back when it still mattered if he died rather than it just being an inconvenience) even after he caused the problem.
Jack's fatherly advice to Ginny who was planning to use Jack to make Harry jealous. Jack sees through this and explains she should just ask him out. She does, and it is adorable.
Jack seems to be the eternal big brother in this fic, always with a kind word or a hug for someone.
Jack finally getting over his Commitment Issues fueled fear of The "I Love You" Stigma and saying it to Ianto without Oblivating him the second time around even
