Quatre's watching him from an angle with a soft smile, which is how he notices the specks on Trowa's sleeve. After a moment of confusion, he traces them up to--

Oh, the glitter. Right. (More pertinent: where it's fallen)

He clears his throat, quietly, and glances away and up.

At Trowa's glance: "Don't mind me," he says, faintly. "I was just admiring your jawline."