Kirby’s whole thing is that he has a huge mouth, and anything he swallows he either absorbs their powers or transforms into. If he swallows Mario in a Smash fight he gets a red hat. In more recent times, if he puts a car in his mouth, he turns into a car.
That’s a neat gameplay idea, but it also leads to questions. What if Kirby swallows a whisk? Or a hammer drill? What if he swallows something dangerous, or something shaped in a way that causes his (presumably) viscous insides to contort in a way that might do him some damage?
Or, most importantly, what if he puts someone hot in his mouth? This last question, at least, was answered at GDC last week, and it was answered in the most definitive way possible, with HAL Laboratory executive director Shinya Kumazaki telling Polygon:
At GDC, you showed superheroes with Kirby. Are those personified versions of Kirby? Or are they superheroes inspired by Kirby?
Kumazaki: That was for the audience to understand what type of hero Kirby thinks of, when he thinks of a hero. So it’s not personified.
A former co-worker (Wired’s Megan Farokhmanesh) attended the GDC panel with me and was struck by the superhero Kirby. She raised an important question: If Kirby swallowed a hot man, would he turn into a hot man?
Kumazaki: I think your friend might have noticed the muscles and power the images depicted. I think Kirby’s ability would be in line with that. And he’d probably have a hat associated with it. But his face would not turn into hot Kirby.
Not sharp angles.
Kumazaki: Still round.
No sharp angles. Still round. But he’s got a hat. Not ideal—I was hoping for more of a “Handsome Squidward” effect here—but it’s also probably what we should have expected given the series’ and character’s history.
You should def go read the full interview, since it also covers similar burning questions like “Will Kirby ever fall in love?”, and “If you cut open Kirby, what would the inside look like?”.