In a medium pot, bring the stock to a boil. Add the couscous, stir, and bring to a boil. Remove from the heat.
In a large pot of boiling water, blanch the asparagus and then transfer to a bowl filled with ice water.
Season the couscous with salt and pepper. Stir in asparagus, cover, and let stand 5 minutes. Fluff with a fork and transfer to a bowl. Stir in the arugula and olive oil, season with salt and pepper, and serve.
