The humming definitely helped, soothing him a bit more just as having Akito holding him as well did. "Y-Yeah." He had been scared, so scared, because that scene had made him almost believe that the other wouldn't make it through what had happened. There had been so much blood...
"I don't know what I would've done." Tsuna bit his lip, eyes shut tightly. "I got so angry after, at the person who made you fight and get hurt." If he was fully aware of how he got when he was angry - namely when he was in Hyper Dying Will Mode - then he would be glad Akito hadn't seen it yet.
"I won't," he said it a lot stronger than was necessary, fingers curling slightly, but this was something important. "I'm not going to leave you. I only left that one time and I regret not being here when you woke up." Speaking of which, how long had he been here then? Had Akito been sleeping that long?