The Anime Freak is probably the most common, and one of the most annoying. You can usually spot a few warning signs to let you identify them before it's too late: they wear the same exact Evangelion shirt every day, they have more than one anime key chain on their person, they wear glasses, they say phrases in Japanese that hey obviously don't understand (such as "Yes! I will never forgive you!"), they refer to you as "-chan", make obscure Japanese culture references during class, and usually fail class. You have to be extremely careful not to let them smell pity or fear on you, because if they do they will immeadiately latch onto you and suck up both your time and patience, leaving only a lifeless husk.Your Classmates Desperate for human companionship, they will invite you to club meetings, anime showings, conventions, and all other sorts of various things you don't care about.
The Know It All typically has a Japanese girlfriend or boyfriend, and because of this "inside source" on Japanese culture, has suddenly become an academic expert on all things Japanese, without ever having read a single book on japan in their entire lives. You can usually spot Know It All's by keeping an eye out for these warning signs: a cocky smile, answering more than their share of questions, getting most questions wrong, questioning the teacher on various subjects and then arguing about the answers (a typical exchange: Student: What does "ohayoo" mean?,Teacher: It means "good morning", Student: That's not what my girlfriend said...), being wrong, talking alot about Japanese food and being wrong, giving long, unnecessarily detailed answers which are wrong, and failing class.