Shangri-La Frontier 4 (manga)

A fast-paced, irreverent adventure for fans of isekai and RPGs! High schooler Rakuro loves hunting down "trash games," but one day he decides to play a AAA VR game called Shangri-La Frontier instead. He creates a character with a bird head, skips the cutscenes and jumps right in--but what awaits him in this game is different from anything he's ever faced... WETHERMON THE TOMBGUARDFresh from hours of level grinding, Sunraku embarks on a quest with fellow gamers Pencilgon and OiKatzo to defeat Wethermon the Tombguard, one of the mighty Seven Colossi.

Pencilgon introduces them to an NPC known as Setsuna of Bygone Days, who begs them to put Wethermon's soul to rest. Though the three friends vow to fulfill Setsuna's wish, the undead swordsman will prove more terrifying than they could ever imagine.