The first word I want to discuss is an artist's name ヤノベケンジ (YANOBE Kenji) which I found on several links on his website such as this one here: http://www.pappa-tara.com/fes/special/interview.html. Because he is a Japanese artist, I was confused why his name was not in Kanji or Hiragana. If his last name was foreign, I would expect it to be written in Katakana, but this is not the case. One of the typical categories of Katakana is emphasis. Emphasize what? One of the textbook descriptions of Katakana said that because foreign loanwords give an impression of sophistication and modernity, Katakana is used to emphasize these attributes. For instance, many people in my group found that Japanese company names were written in Katakana. However, Yanobe Kenji is not a company, he is a human being, so why is he adding "flash"? Out of pretensions that he is such a fantastic artist? I don't think so. Looking at his art, it becomes obvious that his Katakana name coincides with his futuristic art style. You can browse his works here (http://www.yanobe.com/works.html) and see ultramodern cars, machines, and spacesuits. Clearly, he has a direction or "brand" and the same way a company would want to be associated with high-tech, Yanobe Kenji wishes to hint at his artwork's own visionary perspective with his name spelled using Katakana.
The other word I wish to discuss is オバケ, meaning ghost or goblin. I found the word on a Wikipedia article about the manga オバケのQ太郎。Q-tarō is a ghost who lives with the Ōhara family in a manga that was first published in the 1960's. Not being a sound word or loanword, the only other category where it could fit is emphasis, but unlike with my interpretation of Yanobe Kenji above, Q-tarou does not presume an air of sophistication or modernity; he is a cute, rambunctious ghost in a children's manga. The ghost's name starts with a "Q", a loanword manipulated to look like a ghost figure on the cover of the manga, which is eye-catching and creative. The added flash of the "obake" written in Katakana might draw an reader in in the same way. Also even though "obake" is a Japanese rooted word, the character himself is a ghost or an alien entity, so he may deserve to have an foreign-emphasized name.
In both cases, by writing a name in Katakana the reader gains some knowledge about what the person or character might be like. In the first case, he is innovative and futuristic. In the second case, he is strange and exciting.
