The tropes. Enemies-to-lovers, fake dating, and grumpy/sunshine are the best. If I were to write a book one day, it would have to be with these tropes.

The MMC. Aaron Blackford is a heavenly male main character. And I like it when the grumpy/gorgeous guy admits he had feelings for the girl for longer than we knew.

The tension throughout the story. I just had to keep reading and reading.