Maybe the ending of the show will be something like this

The birthing cabins gave me an idea. They show us how any location can work like a severed floor, which is really interesting. It makes me think: What if that is how you do your happy ending? What if that's how you have your cake and eat it too?

Like, Innie mark and outie mark are both as real as eachother. And they both love Helly and Gemma respectively. What if at the end of the show there's a compromise of sorts, like Innie Mark and Innie Helly get a plot of land, with certain days of the week to be their innie selves, and Outie Mark and Gemma get certain days of the week.

The problem with it is that for both versions you are giving up a large chunk of your lifespan. But I can't really imagine a different solution where Innie Mark doesn't die, and he still gets to be with Helly. Reintegration seems pretty lethal and even if it worked, I feel like it's more like creating a new hybrid person than it is like preserving the innie. Not to mention the relationship troubles. Unless a polyamorous relationship is on the table I guess.​