[A lap full of Koby is, Harry decides, one of life's great pleasures. He loops his arms around Koby's waist and watches him work with an expression of bemused interest.

Waistcoat open, he nods as if he's just reviewed an impressive piece of work, then catches Koby's eye.]

Very efficient.

The shirt, I think, may also require attention. And I am quite concerned about your own. After all, I can't have you overheating. You could be injured.