you were watching the fireworks with your friend, Nikolai, when you notice he's humming, then starts singing quietly, out of interest you listen closely, only to realize he's singing Gekka No Yasoukyoku.

" ♪ because it's such a pretty night~ because it's such a sad night~ softly smiling, I'll watch over you~ ♫" Nikolai hums, a wide grin on his face like usual.