There are lot of good reasons to avoid alleys. They’re dark, scary, and filled with pools of water that even the Swamp Thing would raise a scaly green eyebrow towards. But in the Back Bay, there’s at least one really good reason to head to an alley: Casa Romero, a Mexican restaurant tucked in between Newbury and Comm Ave. It’s got a great selection of enchiladas, mezcal, and a hidden courtyard out back.