Snotty scholar geek, kenzan!
Seriously, translators. If there's a bunch of historical names like "Shizuka Gozen" and "Heike Monogatari" in a sentence that you don't understand, throw the darn words into google. Seriously. Three seconds would tell you that Shizuka Gozen's lover was Minamoto no Yoshitune, not a kitsune. It's kind of a subtle difference. Really.