"And what would happen if I teased you so much that you came, say during masturcizing?"
You say that Erica wouldn't take you back as her fiancée, and would only keep you as her tease toy.
"But what if you fell in love with some other girl?" Kara asks quietly, "Wouldn't you rather have a girlfriend who would let you cum more often?"
Yes, you say that is very tempting, but unfortunately your heart is set on Erica.
"That's too bad," says Kara, very quietly.
You don't know what to think, as Kara is acting strangely. But you know that looking at Kara and listening to her talk is getting you closer and closer to the edge, and you know how dangerous that is.
So you turn back to Kara's computer to continue the photo show.