These are never brief. I have a character who's in practically four chapters and this isn't brief.
We are first introduced to Grell as Madame Red's completely ineffectual butler. He tends to hang around the edges of frames, acting generally frazzled and maybe a little ditzy. However, when Sebastian and Ciel set up their trap to catch the notorious serial killer, Jack the Ripper, in action, Grell's true personality is revealed.
Sebastian and Ciel find him standing over a newly-murdered body. Grell at first tries to tell them that he is simply an innocent bystander, but as Sebastian and Ciel were by the only entrance all night, that doesn't really fly. Caught, Grell reveals both his true personality and his true form, that of a flamboyant redheaded shinigami (death god), rather than the meek, black-haired butler.
Grell and Sebastian face off, Grell using his death scythe (modified into a chainsaw, against regulations, of course.) Nearly at the same moment, Madame Red appears, and the truth is revealed: Grell and Angelina were working together to form the serial killer known as Jack the Ripper. However, despite Grell's urging, Madame Red is unable to kill her nephew, Ciel and, at this, Grell proceeds to stab her in the chest with his death scythe. Through the shinigami's power of Cinematic Record (which displays all of a person's memories when they are cut by a death scythe) the reader is shown the backstory of this arc as well as Angelina's motivation for killing the women, which really is neither here nor there.
Back to the battle, then. It lasts for a good long while, but eventually, Sebastian gains the upper hand by (cheating!) stuffing his jacket into the mechanism of Grell's chainsaw, rendering it completely useless. Grell is then beaten to a bloody pulp by Sebastian and is only saved from certain death by the arrival of William, his supervisor at the Shinigami Management Division. Grell is then, very literally, dragged off by William, back to Shinigami headquarters to suffer punishment for breaking countless regulations.
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