Could someone please explain to me the origin of this "common sense" running joke regarding Sanae?

I remember someone drawing Sanae snapped and went "You can't be held back by common sense!" around, naked.
Best girl ever.

Yeah, I remember that too, but was that the first instance, or did it start somewhere else?

http://touhou.wikia.com/wiki/Subterranean_Animism:_Reimu_and_Yukari%27s_Extra

Sanae said:
Oh, did you come to visit the shrine in this cold weather?
Hoho, I know how to give you a proper greeting this time.
You can't let yourself be trapped by common sense in Gensokyo, right?

Thanks, S1eth, that was gonna bother me for a while.

So... is Kanako looking to steal the guy, or scare him off?

Dakkan said:
So... is Kanako looking to steal the guy, or scare him off?

Kanako is definitely looking to steal the guy. Suwako's remark about the eyes is referring to Kanako taking the Moriya shrine.

Damnit, don't leave the SDM! There wasn't even a good scene with Patchy! Ohhhh, how can you go pimping throughout all of Gensokyo, and not go for the best one?!

Forget it, she's wasted on this nameless...