I think his point is that sex is a normal part of living whereas violence is generally not.

For example, the last time I was in a real physical fight was in kindergarten. If I watch/play violent media, it can't affect the way I fight because I do not fight. Sex is something I might actually do though, so overexposure to twisted versions of it could actually color my real world experience.

I still tend to think that most healthy adult minds can easily make the distinction between reality and pretend though.

I don't think it makes them more sexual, but it gives them the wrong idea of what a normal sexual encounter is. The same thing happens with violence, but the majority of people aren't going to engage in direct violence against someone else, so it doesn't matter if they think fights look the same way they do in anime or video games. The discussion is about video games making a normal person into a violent person, not about giving people unrealistic expectations about what happens during violent encounters.

You should also try writing with less question marks, it's condescending, especially when you completely missed the point of this whole conversation.

Something is special about sex. People have sex. People don't kill others (generally). Compare how many people you personally know that have had sex vs how many people you personally know that have killed someone.

As the study above points out, violent videos games don't make you more violent but I'm pretty confident sexy media (games, movies, music, etc) make people more horny and therefore more likely to seek out sex. Also, since sex is something people do in the normal course of their lives (vs violence which is not a normal part of someone's live) the media they consume is more likely to influence their behavior. It's a manual for something they hope to participate in vs violence, something they don't hope to participate in.