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That's perfect. Or "Hearts are like flowers, they both are made of organic matter."
Or "Hearts are like flowers, they both photosynthesize."... um...
Or "hearts are like flowers, without sunshine AND rain, neither will flourish."

hearts are like love? sticky and wet?
hearts pump dust and their hairs are all gray?
hearts are like raccoons. they're super cute until they FUCK YOUR SHIT UP

That works for sure.