Cloak of Nettles

You cause a willing creature within range to grow long barbs from their body. The target gains a +1 bonus to AC. The first time an adjacent creature hits the target with a melee attack or grapples them before the spell ends, they take 1d6 piercing damage. The spell's effect then ends. This spell's damage increases by 1d6 when you reach 5th level (2d6), 11th level (3d6), and 17th level (4d6).