Fire Emblem: Heroes Impact!

It was just your average day. Going to school, dealing with your army of girlfriends, and having to fight Honkai Beasts that threatened to destroy the world.
Oh, and having to deal with other world ending events that were related to the Honkai but were caused by organizations that had their own goals and sneaky motives.

(M/N) thought his life couldn't get any more complicated, what with him attending St, Freya and dealing with overly affectionate Valkyries and trying to get an education.

...It got a lot more complicated when during one battle against the Honkai he is suddenly dragged into a whole new world! A world of Heroes, Gods, bloodshed, and wacky shenanigans.
"Oh, great hero! Please help us!"
"We're honored to have the Great Hero aid us."
"I can't wait to be friends!"
"I'll pop your head off, just like with my dolls."
"Please stop calling me Bruno Mars. My name is Bruno, but that is not my last name."
"I didn't sign up for this! Send me back home!"

Disclaimer: I don't own anything besides my ideas for the book. All credits to their respective owners.