Books are invaluable possessions. If a book contains a good enough tale, it can be passed down from generation to generation, warranting multiple reads and rereads each time it is passed down.

Books are comfort. A well-built world can make a reader forget whatever troubles they may have.

Books are empowering. Books are memorable. Books are works of art.

Twilight Sparkle hasn't read a book in three days.

The universe is like a large complex spiderweb, with each separate pony its own point, connected to the other ponies by the web's various strands. And, like a spiderweb, take one pony out, and the universe becomes a mangled version of what it used to be.

This is the story of a young filly who managed to erase herself and her connections from the universe, from the circumstances that led to her disappearance, to the consequences of her actions.

Everypony knows Rainbow Dash is not only awesome, but also radical and cool.
Everypony knows that poetry is unquestionably none of those things.
Twilight Sparkle doesn't seem to think so, and as such invites Rainbow to an afternoon of poetry, both reading and composing.