I don't know japanese and can't pass tests, and I wouldn't even touch this theme, but lyrics for this song do not exist on any lyrics' websites. I coppied it from niconico hardsubs and wanted to save it somewhere so chose to contribute it here, if you accept. Song is Tooi Yakusoku (遠い約束) by singer Gotou Mayumi (後藤真由実), an opening for FlyingShine's visual novel "Noel".

Japanese lyrics:

愛を教えて
声を聞かせてよ
遠く果てない

揺れる手のひらに 闇を数えたら
君へと続く 記憶の先は 約束の場所

愛を教えてよ
遠く果てなく

遠い君との約束は
哀しみと罪の間に

愛を教えてよ
遠く果てなく

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Romaji lyrics:

ai wo oshiete
koe wo kikaseteyo
tooku hatenai

yureru tenohira ni yami wo kazoetara
kimi he to tsuzuku kioku no saki wa yakusoku no basho

ai wo oshieteyo
tooku hatenaku

tooi kimi to no yakusoku wa
kanashimi to tsumi no aida ni

ai wo oshieteyo
tooku hatenaku