Max is cynical and often negative, while Nikki is wild and adventurous. Their personalities can create a really interesting dynamic. Max might be the voice of reason (although a very grumpy one) when Nikki comes up with her crazy ideas. For example, if Nikki wants to go exploring in a dangerous part of the forest near the camp, Max would be the one to point out all the potential risks.
Nikki's exuberance can sometimes break through Max's tough exterior. She might be able to get him to join in on her fun, even if he initially protests. On the other hand, Max's more reserved nature can ground Nikki a bit. For instance, when Nikki is about to do something really impulsive during a camp activity, Max's dry comments might make her stop and think for a second. Their personalities are like two opposite poles that attract and repel at the same time, making for great fanfic material.