Gratuitous English/Literature

In The Yiddish Policemen's Union, the Jews of Sitka speak Yiddish as their primary language, but prefer to swear in American English.
The Japanese Harry Potter books, in addition to featuring the English title as well as Japanese on the cover, have English romaji beside the kanji for their publishing company - and it's written "Say-zan-sha (Seizansha)."
Lampshaded throughout Chris Jericho's first book, A Lion's Tale, while recounting his times in Japan. He often referred to it as "English just good enough to make no sense."
In the Japanese translations of the Warrior Cats series, the names of the characters, which are usually combinations of nouns, verbs and adjectives, are left in English.