i have seen many parodies in both anime and manga of

a girl running with bread in her mouth and bumping in a guy on corner but where did it come from which series is this parody off?

and anther parody of a delinquent guy helping a dog in rain seen by a girl which manga this originally belongs to?

I think it'll be impossible to track down the original reference for both, since it could easily be an unknown manga and be ancient as manga itself. According to anidb, the earliest anime tagged with "Running with Food in Mouth" is Touch (1985-1987) whose manga (Touch) started in 1981. But I am 99% sure to have seen it in Doraemon (1964-1996), but if I'd not be surprised if someone can name an earlier manga (maybe Sazae-san?).

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What I like in Trivial Pursuit style. Pick your category:

I agree with reid1, even if someone finds an earlier example of these tropes we probably will never be sure they were actually the first to do that. The bread in the mouth one might even come from a real-life habit of some people. The second one probably developed from similar scenes where an apparently mean/evil character is shown caring for an animal just to show they actually aren't so mean. In this case, there isn't a landmark work that started the trend, it is something that evolved.

I might be Jumping the gun, but i think in Sailor Moon something like that was done with out it being a parody... I might be wrong 'cos i haven't seen it in forever... also it might had been in Glass mask since that is THE SHOJO where most cliche come from, but i have never read it...

Aside for what i wrote i'm with the people above me, if there was such a thing in works like Sazae-san (40´) then the manga i told you about most likely isn't the first to do it since it is from the 70´.

ya i guess u r right just wanted to give it a try

I don't know, where the "Girl running with bread in her mouth" originated from, but I think it's popular at the moment because of Kyary Pamyu Pamyus music video Candy:
http://www.youtube.com/watch?v=UoK8DaJRDaM