I don't know much about hentai, yaoi, or yuri myself, so I can't really give you any advice other than the over-use of the same words. Find synonyms of each word you see used often and find a thesaurus or a website that'll give you words with similar meanings.
Other than that, it was just awesome. I could picture everything being played out in my head. Yugi's adorableness and Yami's epicness. :)
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