I like Killing Stalking more because of Sangwoo he is so confusing and unpredictable. Their past is pretty much clear but their future is not. With this manga their past is unclear but kinda of predictable if you read a lot or know a bit of psychology. You can also guess the future in this but the process is slow and entertaining. In killing stalking you don't know what the hell is going to happen each page is a shocker almost. Even though its Yaoi you cant tell if Sangwoo will like Bum romantically in the future. People will always say something is a copy just because it is similar but just because there are similarities doesnt mean one copied the other.
I like Warehouse more than killing stalking. There, i said it. It feels like a deep confesion some how. ( ̄へ ̄)