Place it just before the chorus payoff in a fan edit, then follow it with Anime Wow to sell the reaction, and keep it as the final accent before the next scene cuts in.
O tym dźwięku
This is a sub-second sung note from Marine Houshou, holding a bright 'Le~va' with a steady, regular vibrato that wobbles evenly through the short phrase. It feels playful and theatrical, like a tiny vocal flourish caught mid-song, charming rather than dramatic. It comes from her Hololive singing stream of nostalgic anime songs, at the 19:28 moment.