Asta had passive resistance to curses and HAS negated curses in the past.
He negated the curse bomb that Megicula placed on Lolopechka.
Moreover, he should have enhanced resistance,
especially since he can simply wrap himself in causality break which works on both magic and curses.
Anti-magic is just a name in verse since it's mysterious, but in reality
ant-magic is canoncally derived from anti-energy. Moreover, the
raws specifically refer to it as ćåćØćć«ć®ć¼Anchi enerugÄ« ć and has been shown to negate any form of paranormal or supernatural energy in BC,
whether it be derived from magical power or anything else.
and just to be clear, magical power is just the name for refined mana, to clear
mana is simply defined as fundamental supernatural energy that exist. Magic however, is only one application of magical power, but not the only application.
Gadja can float without using magic (but he's still using maryoku/magical power) and
zetten isn't magic either however it also uses magical power/refined mana. So regardless pacifism isn't really doing anything to Asta.
Curses are explicitly stated to not be magic in BC as they are not derived from magical power. However they can be manipulated by magic/spells.
Curses in BC are explicitly powered by
curses power ćåŖå juryoku ć and magic/spells is power by
magical power magical power ćéå maryokuć
Moreover,
Vanica from the dark triad posses both magical power (maryoku) and curse power (juryoku) so she has two different type of energies that she utilizes to generate curses and magic.
In the capital invasion arc Rhades hit Asta with a curse that made him perpetually bleed from any cut no matter how small or large as a way to counter his anti-magic. What Rhades didn't know was that anti-magic doesn't just negate magic, it can also negate curses
. Asta then used his swords to take out the curse power.
So a lot of the DK's shouldn't really affect Asta at all.