Most Twitherym enemies have names that end with "Twitherym," and "Twitherym" is treated as a plural noun in the text log because there is more than one Twitherym. That's fine and dandy.
However, with the Twitherym Infestation enemy, the "Infestation" part of the name is the subject of the sentence, and "Infestation" is a singular noun. Therefore, the text log should say, "The Twitherym Infestation seems tough," rather than "seem tough." "The Twitherym Infestation readies Tempestuous Upheaval," not "ready Tempestuous Upheaval."
Additionally, I don't know if this happens with all Twitherym, but if it does, they all should have 's added to their names when possessive. Currently, the log displays, "The Twitherym Infestation' Dia effect wears off."
A less important side issue: currently, Artisan Moogles say something to the extent of, "We don't care how far into debt we go into this time!" The second "into" should be deleted, because it corresponds to the same prepositional object ("debt") as the first "into."
Edit: The original post said "Porter Moogle." It's actually the "Artisan Moogle."