It is a sad thing seeing Madoka wince like that. It is hurting her and he never wants Madoka to hurt! He presses on the wound, knowing that it has to hurt a bit so it stops bleeding. But he doesn't like it. He doesn't want her to hurt at all.

He just wants her hurt to go away, so she doesn't have to be sad any more. He holds her hand tightly and stares at the cloth and the blood, wishing he could make the hurt go away with water alone.

His hand started to hurt, at first he doesn't notice, he thinks he is just worried about Madoka and imagining it. But then... There is blood. Blood spilling not from her hand under his but from his hand as a cut appears there, staining his hand red.

And under the cloth, Madoka's own cut closes and vanishes, like it had never been there to begin with.