As far as I can tell, Marten and Hanners would be unable to have a physical relationship. And I really don't think the attempt would be made.
It's unfortunate that in adult relationships touching or intimacy is usually a sticking point.
...Which makes me imagine Jeph doing what a ton of authors do, and start doing side drawings of a funky alternate plotline/time-warp (or strange amnesia ala Final Fantasy
with a chibi-cast (like age 12 maybe) that has adventures. Hanners would be the new but strange girl that nice boy Marten befriends. Hijinks and awkward adolescent pseudosexual tension ensues, and they say the darnedest and cutest things. Might be awesome merch possibilities.
Thank goodness Jeph probably won't do that.
Though who can tell, all things considered.