The game is made with Unity engine (i have no idea why you are getting the virus scan part, if you mean the google drive scan then they do that automatically, most of things are labeled as can't be scanned).
'works with itch io app' : probably not, because it is a zip archive containing PC version and 3 phone apk versions (performance and compatibility based)
Sorry for the late reply, cheers
NK
From what i'm aware both demo and final version on Itch.io are to be downloaded then extracted on local drive and played via launching the exe file (or apk install on phone). I was unable to get the zip to work straight from the Itch io app, maybe if they made some updates from the last time i tested. Also, there might be a way to register the game into the itch io app after it's installed (unzipped), i recommend checking the itch io support forum (https://itch.io/board/24575/butler)
DLsite version (demo and final) : can only be downloaded then unzipped and played.
I hope this helps
