Everyone knows Harlequin, even if it's exclusively from their aunt's bookshelf*. But the well known brand's new KISS series of romance novels is meant to target the bookshelves of a much younger, fresher audience.
The idea here is visual - bookends, dynamically interacting with one another, suggestively alluding to a narrative that exists between the two.
The point being that Harlequin can evolve with the times. Without having to be 50 shades of anything.
*Specifically my aunt's bookshelf.
The first book in the series is actually available online - this was part one of appealing to a younger audience.