The Left Field Bleachers at Target Field are a collection of four sections, 128-131. Though named Bleachers, these seats do have a chair-back. Directly to the left of Section 131 are the Twins and visitors bullpen (visiting team in front, Twins in back).
Unfortunately, the main video board is in behind you and obstructed the the seats above. In addition, your only chance to see the skyline in RF is in the seats closest to the foul pole in 128.