He wants to scout the Plaza

Big boy decides to scout the plaza first. More brothers is always good but if they can't find the raiders it won't matter if he has an army at his back, he won't be able to reclaim his stolen property. He makes plans to set off the next morning instructing Biter to watch the camp, protect his property, and to stay away from Evelyn just like he did before he left this morning. Biter nods and wishes him luck before exiting the tent, presumably to go visit the short haired girl in the cage again.

The image of the two of them rutting from earlier flashes into Big boy's mind and suddenly his cock, which is always at least semi-erect, rises and becomes hard to the point of pain. He hasn't cum in almost 24 hrs and now that he doesn't have anything else to occupy his mind his urges are becoming unbearable. He remembers Evelyn's promise to help and take care of his thing after they debriefed but now that Nora is here she is distracted acclimating her to their Jerry rigged lab and her pathetic intern. Evelyn's diminished scent due to pregnancy is his only saving grace as he battles to keep hold of himself.