Bishoujo Control

Combining the gameplay of an arcade shoot’em’up with watching pretty girls, Bishoujo Control puts you in a spaceship, battling hordes of enemies flying downwards. All that flies is not an enemy, though; you can also shoot at blocks that, when shot, make up a picture of a pretty girl on the right of the screen. Picking up bonuses in the shape of the signs for “pretty girl” powers up your weapon. When all pieces of the picture are picked up, you are given a chance to enjoy the picture at your own pace before progressing to the next level (and the next girl)

Source: TheGamesDB