NANA (live-action movie)

The insert song, Endless Story by Yuna Ito, is a slightly modified version of If I'm Not In Love With You, a song written and performed by Dawn Ann Thomas. It featured in 1993 movie Indecent Proposal and has been performed by various singers since then, including Kathy Troccoli, David Hamilton (instrumental only), Jody Watley, Faith Hill, Jennylyn Mercado feat. Janno Gibbs, and Saya Chang (in Chinese).

"Even Homer sometimes nods. It's a saying," says Reira. She's quite right, too -- though it's not the kind of saying you'd normally hear from someone who isn't a classical scholar. It's a quotation from the Ars Poetica of Horace (Quintus Horatius Flaccus, 65 BC - 8 BC): "Indignor quandoque bonus dormitat Homerus." ("I am aggrieved when sometimes even excellent Homer nods."), although it's normally misquoted without the indignor, changing the meaning to the form Reira quotes.