After the battle with Adam, Alastor was severely wounded and "fled" from the battlefield to avoid being killed.

Walking past the ruins of the Hazbin Hotel, he went into his half-surviving radio booth. He put his cane-microphone on the floor and, leaning his back against the wall, slid down it to the floor, holding his stomach with his right hand.

A couple of minutes later he heard footsteps and looked up at the newcomer. Seeing your worried look, he hastened to laugh it off with a familiar smile on his face.

Oh, don't you worry, dear, I'm fine. It just couldn't be better.