Because they usually have sexy little bodies on them and have a bit of a submissive style to them. Also, they are really nice and gentle for the most part. Also they wear school uniforms which are hot LOL.
There's some kind of mysteriously attracting innocence in their looks. Like they look at lot more defenceless than other women. It kinda boosts guy's natural instinct to be a protector, I can't even explain it.
And same here, I'm simply crazy about Asian girls, especially Japanese.
That's natural - western-type guys find eastern-type women attractive because it's improbable that the two of you would be distant relatives. Nature has made it this way for you to avoid inheritable illnesses.