Well for one thing, you shouldn't look at it as an issue of "32 million surplus men." The hurt is going to be distributed more broadly throughout the entire male population. It's not like things like serial monogamy don't exist in China. What will happen is that relationships will simply be fewer and more far between for the average man than the average woman.
Interestingly, this is actually already the case in Western countries; in the US, there are roughly 55 single men for every 45 single women[0]. This is, of course, due to the younger average marital age of women than men.
Naturally, there's a lot more slack in the system as regards non-marital relationships than marital relationships; in the latter case the gender imbalance will indeed be a fundamental difference between China and other countries. But by the time the dating market shifts conclusively towards marriage, a lot of men will have aged out of the key crime demographic (ie, males aged 15-30, who commit such a hugely disproportionate number of crimes that overall crime rates are mostly a reflection of trends within this group).
I do expect that there will be a little more crime, as well as all kinds of other unpleasant effects that we can't even predict, but it won't be in anything resembling a linear fashion, and a lot will depend on other factors.
>Porn and video games work for a very small percentage of the population that is anti-social anyway.
What do you mean "work?" I'm not saying they can substitute for a real relationship. The relevant comparison isn't porn and video games vs. a living, breathing woman, it's porn and video games vs. jail time. And even if their existence doesn't make crime any less attractive, I think they'll still have an enervating effect that will make at-risk men less of a danger to others.
0: http://www.halfsigma.com/2008/04/unmarried-mal-1.html (look at the bottom row in the table)