Wow, so Sharanla is so much of a parasitic human pest that even death and annihilation of her body are not going to keep her down. In all evidence, she is going to be the leading core and dominant will of the gathering crowd of vengeful souls of the former heroes that Metis and the Four Gods used and discarded. And their growing undead gestalt is already eating people and developing in the next big menace. She has nothing to envy of the most tenacious supervillains.
Glad to see that the MC at long last confessed to his love interests that apparently welcome the idea, even if the shock sent one in a software crash, while the other is probably already planning the wedding.
The author seems to give incredibly inconsistent rules about how the youth potions work, when and how they can be used safely, and how many times. Personally I'd welcome the MC rejuvenating himself for good with its vast resources and magical expertise for the sake of his love interests and transition to a different stage of his life.
The 'middle-aged guy bemoaning his age and feeling inadequate for romance' side of his character concept has really exhausted its narrative usefulness and overstayed its welcome if you ask my opinion. It seems one of those cases when an author puts a gimmick in the title and then feels bound to keep it around beyond any reasonable narrative justification.