It hurt . Terribly . The blonde grimaced as a stream of blood dripped down his arm , splashing onto the floor . Mello gripped his shirt and pulled it over his head , falling back against the wall a moment as the sleeve was peeled off .

Question: What may be the reason why he fell back against the wall ?
Answer: Because it helps the pain .Because the cool wall felt good .Because he lost his balance .Because it eases his anxiety .