Mockingjay spoilers below.
I don’t think romance really belongs in the Hunger Games trilogy,* but if I had to ship something, it would be Katniss and Johanna. At first it just seemed appealing to me because they’re both headstrong, fearless women, but the more I think about it, the more it makes sense.
Compare this ship to Katniss/ Gale and Katniss/ Peeta. Katniss and Gale seem like a good match because Gale inspires passion, emotion, and motivation in Katniss, and the fact that they’re childhood friends who have both lost their fathers gives them a certain understanding of each other that other people don’t—and can’t—have. However, this ship ultimately doesn’t make sense because they lose that last aspect within each other, not to mention that Katniss believes him responsible for Prim’s death (although I do not, but that’s another matter).
It also makes sense that Katniss would choose Peeta (as she does) because, unlike Gale, Peeta understands the trauma of what it was like to be in the Games, and while romance can’t cure PTSD, it makes sense to want someone who is understanding, stoic, and reliable, so I can respect that choice in that sense. Peeta’s relationship with Katniss, however, is born out of a lie, a survival tactic, and ultimately I felt as if there was no real emotion in it—just another way of depending on each other to survive.
Johanna, on the other hand, offers the best of both worlds. Johanna is outspoken, passionate, emotional, and honest (many traits which Katniss loved about Gale, as well as being the best he could offer as a love interest), as well as understanding of pain, trauma, and evil (the best of what Peeta offers). With Peeta (or had she chosen Gale), I feel that Katniss was missing out on something important, even fundamental, in her relationship, but this is not so with Johanna. Add to this the fact that in Mockingjay they become roommates and close friends, it seems to me to be the only ship that makes sense.
*except to show the theatricality of it, as well as to show that we, like the Capitol, can miss the bigger issues because of it, but that’s now what this post is about