Walking on a quit path through a little forest short-cut, Asgore wanted to give a quick courtesy call to Gerson, before arriving at his home. Asgore decided to give the old archeologist the truth and just come clean about why he's paying a visit.
"And after seeing how the darned thing wouldn't come off, I believed the cause to be some sort of magic. So since you've proven to know a lot about such old and strange things, I believe you could help me with this. Would you be so kind as to help me with this please?"
Gerson simply waved off the formality Asgore was presenting and just told him to come over, since they haven't seen each other for a bit and he wanted to catch up with good ol' "King Fluffybuns".
This brought a small smile to the goat-monsters face, being called the funny nickname just warmed his heart. As he hung up the phone, Asgore starts to pick up the pace, already close to Gerson's home.
Right before a sudden-
RUMBLE
Emits from Asgores middle, putting his progress to a halt. Looking down with wide eyes, inspecting his doughy paunch, Asgore swears that he had a hearty breakfast and lunch beforehand. So why does he feel so strange all of a-
GURGLE
This strong surge arises from deep within Asgores gut, with his ringed hand spread onto his belly, his shirt begins to feel tighter around his soft torso. His paunch grows thicker as his pink button-up starts feel smaller and smaller, before slowly stopping. Asgore breathes deep breaths, trying to process what just happened to him. His hands rush around his pudgier gut, feeling around and rubbing his new chubby dome, seeing if there's any damage on the surface.
Then, that surge, that concentrated feeling from before, seems to remain within Asgores stomach. It rushes around inside, he feels it move around like his tank of a gut is an actual water tank. But then, Asgore notices something, it seems to follow where his ringed hand goes. As the burly monster thinks on this, he notices the ring is aglow, inscription becoming bright.
Asgore brings the ring up to his face to inspect this, but as he tries to read the ring, the feeling within dips down then shoots up through Asgores chest and throat. Surging into Asgores head, his eyes, mouth, ears, brain and mind, leaving him feeling dizzy, not realising how he rubs his head with his ring hand. Glowing brighter and hotter, the magic within the ring goes through Asgores finger, and into his head.
These powers and magics culminate into a feeling of ecstasy, and slowly sink into Asgores throat. But he catches it, leaving him with two options: