Benny: So, how does this ProtonMail work?
Darcy: It's an end-to-end encrypted service, so whenever you send an email, your browser or provided creates 2 encrypted RSA keys. One stays on your computer and the other one is sent to the recipient. 
Cory: I don't get it. 
Benny: Sry, me neither. 
Darcy: Watch this <file_video>
Cory: Oh! That's more like it. 
Benny: So except me and the other person no one else can read my messages?
Darcy: Nope. Not the internet provider, not the service provider, not a hacker and not even the government. 
Cory: Why would I use it? I don't have anything to hide.
Darcy: Not even photos you're ashamed of?
Cory: Well, maybe...
Darcy explains to Benny and Cory how the ProtonMail works. Cory has nothing to hide apart from his photos.