Funny enough, over on instagram someone commented "Hi Mr. Bendis. I LOVE your legion stories and could not wait for what comes next. I do have one question though: are you trying to ship Saturn Girl and Jon Kent? I can totally see them being a couple lol. What do you think?"
And he replied "you may feel differently at the end of issue three. Stay tuned :-)"
Sounds like regardless of what goes down, we're likely going to get some info on either Saturn Girl's or Jon's sexuality that renders the likelihood of the two of them being together very small. Or she's already in a relationship, or either are interested in someone else.
https://www.instagram.com/p/B6UEOcGpLKo/