"Dad, can you do me a favor?" "Yes, of course darling, anything." "Will you erase my mind?"
Even more horrible for Drac, knowing that he actually can.
Him reading Martha's gift to Mavis also gets you.
And this utterly heartwrenching exchange:
Mavis: I thought we zinged, Dad.
Dracula: [surprised] You and Johnny?
Mavis: I guess it was only me. But you should be happy, Dad. There's no reason for me to leave. I have no more dreams. I'm just like you now.
The backstory that reveals Drac's wife was killed by humans. It's a gut-wrenching sequence, and it suddenly puts all of Drac's overprotectiveness, obsessive secrecy, and hatred of humans into incredibly sharp clarity.
Dracula: The legend is wrong.
Jonathan lying to Mavis about how he doesn't want to be with her and that he hates monsters. The look on her face just screams heartbreaking.