Lyric discussion by SnakeSoliloquy 

"I watch you when you are sleeping"

No, the speaker is not a stalker. "watch" is as in "watch over" as in protect When one is asleep, one is unconscious and unaware. Thus: I protect you when you're not aware of things or basically it conveys a sense that the speaker is there for the loved one

@SnakeSoliloquy Yeah, I see it as just a sweet, innocent love song, no particularly complex interpretation warranted.

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