"Kiyoshi Kono Yoru" is the famous Christmas classic "Silent Night" from 1818

Momoclo accompanied themselves on the guitar singing it in the fourth
"Sakazaki Kounosuke no Momoiro Folk Mura" episode in 2014

Mus: Franz Xaver Gruber, Lyr: Yasushi Yoshiki (由木康),
John Freeman Young, Joseph Mohr

TV version:

Kanji

きよしこのよる　
ほしはひかり
すくいのみこは　
みははのむねに
ねむりたもう　
ゆめやすく

Silent night
Holy night
All is calm
All is bright
Round you virgin mother and child
Holy infant so tender and mild
Sleep in heavenly peace
Sleep in heavenly peace

Romaji

Kiyoshi kono yoru
Hoshi wa hikari
Sukui no miko wa
Mi haha no mune ni
Nemurita mou
Yume yasuku

Silent night
Holy night
All is calm
All is bright
Round you virgin mother and child
Holy infant so tender and mild
Sleep in heavenly peace
Sleep in heavenly peace

Translation

On this pure night
the stars are shining
Child who will save us,
sleep at your
mother's breast
dreaming peacefully

Silent night
Holy night
All is calm
All is bright
Round you virgin mother and child
Holy infant so tender and mild
Sleep in heavenly peace
Sleep in heavenly peace