MTL - I Have a “System” Halo - Chapter 18 I have a "vanity" halo

I am Master Siwei, and I speak for arcane arts.
This is an era of heroes and heroines.
This is an era of great changes.
In the end, it will be an arcane era opened by me.

- Description from Novelupdates

There was a time when I used to think, “How nice would it be if I got transported into a novel world?”Yeah, I know, it sounds childish—but who cares?It was just a passing thought. I never imagined those silly wishes would actually come true.And yet, I opened my eyes to find myself possessed by the villain of a romance fantasy novel.Not just fantasy—romance fantasy.The worst part? I wasn’t even the main villain, just a stepping stone for the female protagonist… who also happened to be my fiancée.Thankfully, the engagement was broken off, and I thought I could fade into the background as a mob character, ruined by the plot.…But for some reason, the female lead won’t let me go.

A boy wakes up with omnitrix as a X-GENE

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…!?