Toriel (the one in the green dress) is the goddess of life and sans (the one in the black hooded robe) is the god of death, and toriel helped sans get back quite a bit of his sanity and actually made him nicer then before.
@Abdalla1234 isn't Tristan supposed to have Divine Light + Demonic Darkness?? I mean his parents were Demon king's most ruthless son and Daughter of Supreme Deity.