Annin-sama has been revealed as the Pyre Keeper of Mt. Gogyo's Eightfold Furnace. Cryptically, she insists that it's interesting that Goku and Chichi would throw the world into chaos to save a single life. Goku doesn't care about whatever she's on about (having no patience for her Lord of the Rings double talk), and Gohan scolds him. Annin takes a different approach.
"This is good. Want a bite?"
"Get that outta my face!"
When Goku isn't hungry, you know shit is fucking serious.
Gohan and Chichi both apologize for Goku, but Goku isn't having it. Annin chucks her bowl at him, and he dodges it easily... though it shatters a boulder some distance behind Goku, displaying Annin's greater than average strength. Annin tells Goku that if he wants the fire out so badly, to turn it off himself, pointing him toward the valve. Goku makes for it, but Gohan desperately tries to stop him! Goku brushes his grandfather aside, and furiously Annin comes to his defense!!
"Go have a look at the pan on the Eightfold Furnace!" Annin shouts as she chucks Goku toward that very pan.
It is revealed by Annin and Gohan the true purpose of the Eightfold Furnace. The mist that rises from the flames is the very gateway between This World and the Next World. Were the flames stopped, it would take 2000 years to get them started once again... 2000 years of spirits unable to rest peacefully. Chichi begs Annin... there must be SOMETHING she can do! "There is something I can do..."
And she attacks Goku without mercy...!!
But Goku is the student of Kame Sen'nin, Karin-sama, and Mr. Popo!!
"Goku!! What are you thinking?!" Gohan bellows.
(Uh, gee, I dunno, Jiichan... self defense?)
"Annin-sama has been the Pyre Keeper and caretaker of the Eightfold Furnace for tens of thousands of years!" He continues.
"Eeehh?! Tens of thousands of years?! That makes her an old lady then..."
"NOW YOU'VE DONE IT!" Annin spits.
"You just said something you shouldn't have!"
After countering Annin's gust attack with a swing from the Basho Fan, Annin tells them that there is a way to save Gyumao after all! Using the Basho Fan, Goku can part the flames long enough to patch the hole in the bottom of the Eightfold Furnace. It'll be dangerous, though! If Goku takes too long, he'll be swallowed whole by the flames!! But they'll need two rare, special items to patch the hole... a piece of a Fire-Eating Bird's egg to cover the hole, and octagonal beehive honey to seal it.
WHERE EVER WILL THEY FIND THESE THINGS???
Chichi has 'em both.
Goku drops down into the furnace, after cutting the fire in two with the Basho Fan. He quickly finds the hole and fills it with egg and goop (something he'll be doing again during his and Chichi's honeymoon). But as Goku leaps out of the tremendous Eightfold Furnace, it becomes clear he won't make it in time... his own Bukujutsu too slow for the rapidly collapsing flame...!!
With the power of Nyoibo, Goku escapes from the Eightfold Furnace unscathed!! But better yet, Gyumao and Mt. Frypan are saved!!
"GOKU-SA!! I'm so glad you're alive!"
With their deed complete, Annin thanks them and apologizes sincerely for the trouble. Now it's time to say goodbye to Son Gohan and head back to Gyumao!
"This was your first ordeal as husband and wife! Live in happiness!"
"You too, Gramps! Live happily together with Annin-sama!"
(I ship them so hard.)
Gyumao and Chichi's mother's dress remain unharmed.
"Chichi... you're so beautiful." Gyumao sobs. "Just as beautiful as your mother was..."
"Thank you for the wedding dress, papa. I'll never forget this!"
Gyumao says to Goku, "Goku, please take good care of Chichi."
The wedding of Mr. and Mrs. Son Goku goes off without a hitch. What could the future hold for the happy couple?
Uranai Baba's not telling!!