Courting Disaster, my weekly comic about sex, love, and relationships updates every Friday. You’ll laugh your pants off.

This week’s question…

A reader writes… Q: My fiancee and I are in our late 20s. We have been living together for two years. I love her a lot. She is very intelligent, and I find her very attractive. The problem? Let’s just say that in bed, I have had better. Many of our sessions end without me “finishing.” She had noticed this and asked me if she still excites me. I tried to fix things by fantasizing about other women during sex, but that only worked a few times. Then, things changed on our last visit to her parents. I was blown away by her 18-year-old sister. She was wearing a tramped-out Catholic schoolgirl outfit. I immediately began fantasizing about her. The results were amazing. The last month or so, our sex sessions have been great. My fiancee has noticed the difference. She is now a detective, inquiring about the changes. I don’t know what to tell her. She once commented, when I asked her to dress up certain ways, that she could “just borrow these clothes from her sister instead of buying them.” Does she know something? What do I tell her if she persists? I worry that if I play stupid, she will grow very suspicious that I’m doing something besides having fantasies.

Go on over and offer some advice.