Magical★Explorer - Chapter 67 - Nanami 4

Shuu is a member of the literary club that can’t write. One day, he gets a mysterious message on his phone from a girl called Eina, and from that impulsive contact, they begin to exchange messages. They talk of things like their shared interest in novels and grow close. However, when they try and meet, they discover a shocking truth. Eina lives… not in the present, but five years in the past! How will their love develop, parted by five years of nights…!?

This was a fragmented and disorganized world, this was a place that had been forgotten.

[WARNING: MATURE CONTENT]

A story of time-travel. Sly and cunning, she unexpectedly became a sickly noble lady whose fiancé is merciless and demotes her to a lowly concubine. She sneers and bravely breaks off the engagement. To hell with scumbags, marry heirs to lords, blind the courts with her brilliance.