I figured this would happen if they met as a result of a time traveling accident. The other idea I had was where Spike says he needs to watch is weight for the next ten years and then immediately gets distracted by some nearby gems that he consumes while Future Spike rolls his eyes at the irony of it. XD

With the complaints I've gotten about my grownup Spike being so plump, I figured the whole thing having to do with being coldblooded is a good enough argument. Either way, it's just the style I draw grownup Spike in and I love it.

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