Saiki Junichi

The protagonist is a player of a VRMMOFPS game who ends up falling off the map, and ends up being transported to a fantasy world retaining his in game equipment and user interface.

Eri Yukizaki, is a girl locked in battle with a chain-saw wielding incarnation of true evil. But like the demons that boil inside her heart, the 'Chainsaw Man' doesn't seem to die no matter how much she stabs him. As she fights, a young man, Yamamoto watches, love-struck, wishing he could be more than just her useless bicycle courier. An action-packed romance, digging into the human psyche, exploring the demons that buries us in sadness and misery. Hilarious, action-packed, romantic, thrilling, cute, and dramatic!

"Roar, my soul!" the heretics lamented. And the avenger vowed to sing a song of sorrow.