Natalie and Misty
Yellowjackets is slowly unraveling how the relationship between Natalie and Misty as adults makes any sense. They were not close as teenagers before the plane crashed, and they really did not spend much time together in the early days of survival. Season two offers slightly more insight when Misty saves Natalie from helping Javi, which allows the starving group to be satisfied with Javi's death, as him being chosen by the Wilderness. When Lottie crowns Natalie as the leader, that adds another layer to adult Misty's devotion as well, given how, as adults, Misty latches onto Natalie more so than anyone else. But, season three finally delivers the final blow in a moment that delivers a massive payoff from season one.
Misty had never wanted anyone to know that she destroyed the plane's transponder, which could have offered the group a way home earlier, especially after Crystal was so horrified upon Misty's admission. But in the penultimate episode of season three, Natalie follows Misty to the tree where she hid the transponder and discovers the horrifying truth. Natalie's discovery explains a lot, such as why she, as an adult, is immediately ready to assume that Misty was the person behind the postcards with the Wilderness symbol on them, and that her awareness that Misty was likely responsible for messing with her car. Yet, Misty's loyalty to Natalie does not make as much sense until the revelation that Natalie, at least at this point, does not inform anyone else that Misty had the plane transponder, with the potential exception of Van. Natalie and Misty, along with Van, also worked together to use the broken phone the frog scientists brought with them with the parts from the transponder to get a working signal that could alert the outside world to them all still being alive.
Misty is devastated by Natalie's death at the beginning of season three, and even hallucinates her briefly, as well as wearing her black leather jacket. While Misty's connection to Natalie could be previously described as Misty being desperate for friendship and connection and Natalie being most willing to allow Misty's involvement, showing another layer to their dynamic in the Wilderness ensures that their messy dynamic has become a two-way street, with Natalie helping to hide Misty's secret, rather than Misty having a one-sided obsession. There is a deeper understanding between the two of them that finally comes to light with "How The Story Ends" and "Full Circle."