Arcane Absorption

You are so in tune with the arcane, that when you are hit with a spell, you are able to partially absorb it, and dish it back out.

Whenever you are hit by a spell, or fail a saving throw against a spell, you are able to cast it on your next turn, provided you have a spell slot for it.
You can do this a number of times per long rest equal to your proficiency modifier

As well as this, your attunement to the sensation of magic makes you proficient in arcana