[Reborn!] I Get to Watch the Good-for-Nothing Complain Every Day

She spends every day using her life to make snarky remarks. Her codename is Black Cat, and her job is cleaner (?). Her traits: good-for-nothing, snarky, and expressionless. To prove her innocence, she's forced to travel from Italy to Japan and watch over some mafia family's heir as he grows up and... dies. I mean, grows up. “Hello, candidate for the Tenth Vongola boss. I'm here to watch you get killed.” “Wait, what are you talking about? I don't want to die yet! QAQ” Afterward, the good-for-nothing girl got a bump on her head from a heavy blow. “Bite to death!” “Sorry, I'm just a microorganism. I won't question your language skills again. Wait, don't be so brutal--” Afterward, the good-for-nothing girl had her HP reduced to zero once more. “Why does that baby have such a huge head, and why is he only two heads tall...?” “Click--” The sound of a bullet being chambered. Afterward, the good-for-nothing girl got herself killed once again. The good-for-nothing girl gets herself into trouble every day, spending her time making snarky comments and getting snarked at. Life is beautiful, hmm. This story has a snarky, comedic style and won't always take itself seriously. There is no pairing for now. If that's not your thing, please read with caution. The heroine is extremely good-for-nothing, but she'll grow and gain some abilities. She won't be overpowered, though. The author is sensitive, so please be gentle with your criticism. *On 2014.8.24, the author's asides were removed from the story and typos were corrected.