Re: What does " I'm gonna getcha good" actually mean?
The answer lies in the first two lines of the song: "Don't wantcha (= want you) for the weekend, don't wantcha for a night, I'm only interested if I can have you for life, yeah,"
So, "Oh, I'm gonna getcha, I'm gonna getcha real good" means something like "I am going to get you thoroughly" - "I am going to make certain that you become my love(r) for ever".
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