There are five "hidden" CGs that do not unlock through the usual means (reading a chapter or doing well enough in a minigame).
All of these CGs are explicit, and so you'll want to install the patch before unlocking them, but you technically can unlock them in an unpatch game.
- Falling Into Place: Click the word "evocative" in the sentence "No matter how much he was used to the fact that Adam slept practically naked by now, he still finds it unfairly evocative."
- Family: When Nick calls at the beginning, keep him on the phone for an hour
- Just A Note: When facetiming with Nick while Adam is over, keep him on the phone for an hour
- Fondness: Click the word "inappropriate" in the sentence "I think there's no topic of discussion that's inappropriate or out of line between us."
- Lifeline: Click the word "comfortable" in the sentence "...and feels himself start to relax as the five of them settle into remarkably comfortable conversation."
The clicking-based unlocks must be clicked before progressing further in the appropriate chapter (even if the word is still visible onscreen). The "Family" unlock has a time indicator on the phone, while the "Just A Note" one doesn't... just stay on the screen while Nick on the phone is visible alongside Adam.
Enjoy!