Ange was actually the best at this kind of monotonous, repetitive, and tedious work, easily able to amuse himself for a thousand years with it.
Amidst the immersion of copious amounts of the breath of death, bone dust could even be considered the best construction material, bar none. Ange could directly manipulate it to slowly grow, forming frameworks, supports, braces, and even pores.
There would be some holes in the bones, which normally would not affect the bones' hardness but rather lessen their weight and allow the skin, muscles, and fascia to attach better onto them, so not all holes indicated porous bones.
Of course, that applied to normal white bones. When it came to gray bone, silver, gold, and mourning versions, the holes did indeed affect hardness, so Ange had filled all these holes in his own bones.
The weight of his bones reached a hefty seventy to eighty kilograms, over four to five times that of normal bones.