At first, the opening pages of the new manga Grim Reaper Online appear to just be another blatant ripoff of Sword Art Online, but everything changes when a Grim Reaper gets sucked into that world's virtual reality MMORPG, adding an element of Black Butler to the tale.
Written by 쑨, the Grim Reaper Online manga introduces tragedy fairly early on in the debut issue when a girl who finds solace in the friendships she makes in an MMORPG gets ruthlessly beat up by those same comrades upon learning who she is in real life. Their terrifying demeanor, disgusting language, and brutal methods of killing her character in the game are so realistic and traumatizing that the actual player dies of a heart attack.
When the Grim Reaper or, jug-eum-ui sin, comes to take her soul away, the manner by which he gets sucked into the game feels akin to Sword Art Online. In Sword Art Online, thousands of characters playing the eponymous game find themselves trapped inside and are only able to escape once they defeat the boss on the 100th floor of a castle. Similarly, in Grim Reaper Online, chains shoot forth from the girl's headset and wrap around the Grim Reaper upon his arrival before pulling him into the game, making it appear as though he is definitely trapped inside, especially as there's no headset for him to take off to disconnect from the game.
Meanwhile, the similarities between Grim Reaper Online and Black Butler are pretty self-explanatory as reapers play a predominant role in both. Much like the reapers in Black Butler, the jug-eum-ui sin in Grim Reaper Online originally plays a neutral role, as his sole purpose in the manga is to take the girl's soul away, which, based on his initial reaction upon finding her lifeless body, sometimes requires him to do so by force, similarly to how Grim Reapers in Black Butler reap souls with their Death Scythes if the humans they find deserve to die.
One Grim Reaper from Black Butler, Grell Sutcliff, can be compared to the jug-eum-ui sin, although their characters are quite different. Grell is portrayed as clumsy and awkward throughout a great deal of the series, which jug-eum-ui sin appears to be as well but only because he's unaware that he's been sucked into a game. For example, he tries attacking permeable scrolls containing gaming information when they appear before him, thinking they're demons.
Black Butler and Sword Art Online aside, the concept of a grim reaper unknowingly getting trapped inside an MMORPG is quite original, which helps the manga stand out from the overabundance of similar stories that transpire in massive RPG worlds. While obviously amusing, how this grim reaper will react when he inevitably discovers where he is and how his powers will manifest in the game are enough to keep even those bored with these types of series interested in Grim Reaper Online.