It's... really wistful and a little bittersweet, isn't it?

[ He makes a sound of thought, and his hand stops: he quietly hums some of the melody back and brings his hand up in a loose fist against his mouth. Despite the shyness of his pose, he's very businesslike when he speaks. ]

I can do it. Ah--write the rest. Lyrics might be a bit tough...? It sounds personal, though... you're sure Viktor-san would be okay with this?