Ai Senshi Nikoru is a top down, action shooter. You play as titular character Nicol, as he fights through a horde of aliens to save his abducted girlfriend. Armed with only a blaster, he must fight his way through 7 levels to be reunited with his loved one.
In order to progress, you must search each stage for three crystals. Once these are collected, you're shuttled off to the next area. Power-ups are scattered through each of the stages, some have permanent effects, such as increasing the power of your weapon, while others serve as temporary armor. Along the way, you'll be impeded by sub-bosses, traps, and bottomless pits that send you to the underworld.