"Do not fuck with me, I have a titan girlfriend and a giant shadow wind demon thing on my side!! AAAAAAAHHHH"
instead of the typical "MC travels into fantasy world," the Demon Queen travels to MC's world.
There's no summary so here's a bad one:
MC goes on train with friends, falls asleep, wakes up alone, gets chased by monster welcome party, falls down hole like Alice in Wonderland, and meets Frankenstein's monster girl who becomes her wife because its part of the laws of this world. They're a cute couple getting to know each other as they navigate cohabitation and she also learns more about the town in general.
All of Humanity is Yuri Except For Me