Justin meets a girl on the World Wide Wiz-Web who seems nice enough... except that she's a werewolf.
Did You Know?
In this episode we are told that if someone kisses a werewolf then they will turn into one as well (which is how Justin turns into a werewolf). However, in later seasons, when Alex Russo starts dating Mason (a werewolf) she never turns into a werewolf, even after they do kiss. This is actually explained when they're talking to Mason about it, he says that this effect only applies to "mutt" werewolves. Purebred werewolves such as himself do not have this limitation. See more
That's a stereotype. Just like how we change during a full moon. We change every night.