Debate me all you want on whether all this is shippery or not. But I'm putting it here anyway, either way.
-"It might be the only chance we get."
"We?"
From the very beginning, for whatever reason, Aeryn includes John in her escape plans.
-When Crais is questioning John, Aeryn speaks up to defend him- although she does place a little insult in there when she does it... Not to mention that also leads her to be "irreversibly contaminated," a sentence which calls for her death.
-"We take her, too." paired with, "If she stays, we all stay."
Whether John was just being the Good Guy or not, he was not about to leave Aeryn there for Crais to have her killed. And that just completely floored her to have him say that.
-"You can be more."
I love those four words. John actually believed in her that she could be more than just a chick with a gun.