You were not born with innate magic ability. No. Rather your magical power stems from a ritual. This ritual was created by a group of individuals who sought to destroy the arcane, only to learn that to reach their goal they had to embrace what they hated. While some who choose this path walk it alone many often band together for a common goal and create small sects. What drove you to perform this ritual? What fuels your hatred of the arcane? Perhaps a wizard neglected to heal your dying mother and now you seek revenge. Or maybe you are a teifling who seeks to wipe out the creatures that cursed your lineage?

Counter

Starting at level one you gain the ability to counter opposing magic. When a creature you see casts a spell you may use your reaction and expend a spell slot of your choice of level. If the level of the spell being cast is equal to or less than the level of the spell slot you used the spell is countered. Otherwise the spell is not countered. Cantrips count as first-level spells in this regard.

Absorb

When you attempt to use your Counter you can try to absorb the cast spell instead, gaining either one free use of the absorbed spell at the level it was cast, or a number of sorcery points equal to the absorbed spells level. Absorbed cantrips are cast at their base level and count as first-level spells in this regard.

Anti-magic Aura

You can use your bonus action to expend a spell slot and for one minute spells up to that level that target you have no effect on you. (For example, magic missile would have no effect. Fireball would however.) You can use this feature a number of times equal to your charisma modifier (minimum of one) and regain all uses after a long rest. 

Anti-magic field

As a bonus action you can create a 30ft radius sphere centered around yourself that lasts for one minute. Creatures you choose inside this field can not cast magic spells. You can use this once per long rest.