wow i can see bunch of "white knights" jumping onto a bandwagon to curse this calvin guy, as if he is the worst person ever walk on Earth.
while it's not right for a person to assault another person (female or male), there must be reason for this guy to react that way.
we can't really judge until we know the full story, can we? both of them could be wrong, unless we know that he is a drunkard who physically abuses his gf regularly.