Unfuckable is the penis useless to fuck, not because the lack of erection, but due to its very small size, equal or inferior to 4 cm ( or 2 inches ) when erect, turning impossible the intercourse in the vagina ( ups and downs), to achieve the orgasm. In such cases, to obtain it, is necessary to use a penis pump to masturbate. The same occur with the buried ( in the pelvis) penises. Many times, the improper size refers only to the length of the organ, not the girth, that can be large ( only a big head outside the pelvis, but totally useless to move ).
" His unfuckable penis has a big mushroom head, but its length is only the length of that head, without a exterior shaft to sustain it."