[His tone makes Aziraphale concerned. :( Since he doesn't know which options Karkat has heard yet, he lists them all.]

You may return to your life for a second chance, move on to the afterlife, or stay here as a warden yourself and make your own wish. It's up to you. [A moment's silence, then he offers,] I will support you in whatever you wish, Mr. Vantas. It's your fate in the balance and hardly my place to interfere.