This book is also known as Re: The Old Hero's Journey, I'm a Lesbian, but Everyone Around Me Is a Monster!, and The Heroine and Her Overlord-Brand Lantern Holder~
"It's... over..."
After defeating the monsters and saving the world, a hero named Molly returned to her own world...
Then she discovered that while she'd spent over a hundred years in another world, the same amount of time had passed on Earth!
"Ah... I really am beyond saving, aren't I..."
A little thing like reality can't defeat a hero! After some hard work, the hero became a shut-in with a comfortable income and got hopelessly addicted to RPGs.
"...Don't worry. I'll stay with you until the very end..."
Then the hero's favorite game inexplicably faced an impending shutdown. Molly decided to wait for the game's end alongside the last remaining player in her guild.
But... shutdown time arrived... and something seemed to go wrong?
"Another other world!? If you make me fight the Demon King again, I swear I'll join the enemy!!!"
"Erlona, what did you just say?"
"Nothing... Don't mind me. Just forget what I said, like an idiot who can only remember things for the blink of an eye, or a veteran who gets beaten up by newbies and never learns. That's right, Momo-idiot."
"The most urgent thing is to check what's going on outside the guild headquarters of Ainz Ooal Gown..." Though... I already have a pretty good idea...
When the hero girl realized that not only she and the guild's one remaining member, but even the entire guild headquarters had transmigrated to another world, she calmed down. At worst, she'd just have to struggle for another hundred years or so... Wait, what?!
"Time... has reset?!"
"A royal selection between five beautiful girls?"
"A Sword Saint born with more than thirty divine protections?"
"The Witch Cult? You're kidding! I could almost believe the stuff before this, but this one's clearly the FFF Brigade!"
Just what kind of world is this...?