To think Lucifer's always quietly concerned with being the toxic one between the two of them. That love could be a corruptible force shouldn't be surprising to him of all people, isn't that arguably what fueled and warped him with his Father?

It's maybe this reason alone that he acknowleges Istredd has a point.

"I know waiting may make it worse but... I think doing it while we're both," look he's finally putting voice to his own state!, "unstable is unwise."