Who's the other girl?

Sonya and I watched the new episode of Coupling last night. [Spoiler] It ended with Susan giving Jane a big, tongue-filled kiss to get Jane out of a date with Oliver, the new character. Steve, Susan's boyfriend, saw all this and thought it was pretty great.

"How would you feel if I kissed some other woman?" Sonya asked me.

"Well," I responded, "who's the other woman?"

"Does it matter? How would you feel?"

I thought about it for a minute.

"I'm not comfortable making a general ruling on that," I finally said, "that's something I'd have to deal with on a case-by-case basis."