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In Katekyo Hitman Reborn!, Xanxus tends to do this when he reaches the apex of his fury (along with breaking out with his old scars). To quote just one instance:
Xanxus: Shit... shit... piece of shit... you trash!
Well, what else would you expect from the Sin of Wrath?
In one chapter of Keroro Gunsou, Keroro gets sick, and Tamama tries to visit him with gifts, hoping that by this point he's getting sick of "that dumb broad" (Angol Moa, whom he regards as a rival for the Sergeant's attention) trying to minister to him. Instead, he finds Moa is merely sitting quietly with Keroro at his bedside, upon which Moa politely asks Tamama to be quiet so Keroro can sleep. The flabbergasted Tamama simply babbles "My electrolytic quotient has been reduced to the laxity of damaged hair..."
Rurouni Kenshin: While looking for Kenshin, Kaoru happens to go to the restaurant owned by Misao's grandfather (and he's staying with them). Hilarity Ensues as she realizes that Misao knows Kenshin: they crash their foreheads into one another (twice!) during their conversation, causing both of them to exclaim wordless pain. (The word bubbles are just in wingdings.)