Could the fruit be a tontatta fruit? their tails kinda remind me of squirrels
Tontatta are extremely strong for their size, maybe an ancient giant would be able to destroy the world with a fruit that allows them to become one because of all that muscle mass concentrated in such a small package. Like how Don Chinjao's head could crack the ice continent a tontatta with all that strength could probably crack the red line. The giants have a "spear" move that they boast can pierce anything but the red line/bloody serpent, if they could refine it to a sharp point that is much smaller than the giant blast they use they might actually be able to pierce it.
Just a squirrel would be funny too. But I have always wondered if the big and little folk were connected.