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A short gag "series" that Clamp draws in various magazines. Each involves xxxHOLiC and another CLAMP title.
Characters from various Type-Moon franchises, such as Fate, Tsukihime, and Kara no Kyoukai are able to hang out at the strange cafe called Ahnen Erbe. They chat together and deal with various curiosities such as a nosy talking cat or a "pot of happiness," which expels a gas that causes people to laugh.