I should be more clear. The stupid child hood thing would be killing 1 or 2 cats, realizing how awful it was and stopping. If this is a person or persons they are clearly having much fun with this just due to the sheer amount of effort they must be expending.
Oh, I understood what you meant, though I never could stomach that sort of thing even when I was a kid. It’s the classic serial killer behavioral pattern to begin by “practicing” on pets.