Back when Percy and Annabeth started dating and before got separated, the couple have a matching gray streak which they got for holding the sky. It like a natural mark of belonging (as I called it) between the two. And it matches with Annabeth's eyes too.

But after the trip to Alaska, the gorgon's blood somehow make the mark faded.

Annabeth pretty disappointed. Percy, being the best boyfriend ever, see through it. He secretly go to a hairdresser and dyed one streak of hair to gray. He somehow made it permanent (maybe by using his control over liquid). Annabeth was over the cloud for what he has done.

Later on, Annabeth think of the her gray streak...

It do matched with my eyes pretty well... but not with Percy's...hmmm...

And so they got another permanent colored hair streak. But this time, it was Sea green. They cherish those streaks forever later on...

Dis idea was pretty random...
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