In the universe, for every action there is an equal and opposite reaction. matching energy.
@Jeruba asked a pertinent question. What is “on read”?
If you are wondering what it means when a guy leaves one of your messages unread, it could mean a few things. It could mean he is playing some cutsie little game. This is not likely as that is not usually how guys are. It could mean he has been too busy to check messages. It could mean he saw it was from you and decided not to even read it. I think that one is pretty clear what is meant. He’s ghosting you.
“on read” I guess could also mean he opened it and never closed it…it is in the “read” position. I guess if that is the case I’d say either he is thinking of just the right reply (again, not likely as that is not how guys operate) or he just didn’t close it yet for whatever reason. Laziness would be my first thought.