Farticular Situation

Often while driving ride share (Lyft/Uber), I find myself in a particular situation. To be more precise, a farticular situation. It's 4:03am, and I've just picked up someone who's on their way to work. The situation arises (literally) when I'm in my car with one other person. Windows closed in my perfectly climate controlled vehicle, I smell it. Someone, without a doubt, farted. At this point, there is no question as to who dealt it. Because I, most definitely, did not do it. Now, I get it, people fart. Hell, I would imagine, in one way or another, most things do. But, that in no way diminishes the fact that now currently in my car are me, you and your new friend…Stinky. And sometimes old Stinky decides not to go with you when you get out of the car. Stinky stays and you say nothing. Not even a tip. Then, the real challenge is to get Stinky out of the car before the next rider gets in. You can't really spray because of potential allergies and such. Wind down the windows and blast it but that doesn't always work. I find myself in a Farticular Situation (Part II). Do I act like nothing's happened and let the next passenger think that Stinky's with me? Or do I introduce Stinky as the friend that the previous rider left behind? I find that it depends on Stinky's personality. Because it's an awkward conversation, not entered lightly. And while this has now been a regular occurrence, I'm at odds with how to deal. Because with Stinky, it's always round trip. What the hell wouldyoudo?