Denno Tenshi: Digital Angel

Four beautiful sisters - Foltjunia, Eindebelle, Leamuroda, and Crealidelle - fight an evil alien race known as Bestia in deep space, transforming into powerful robotic machines. One day, Foltjunia is attacked and ends up unconscious on the pavement in one of the cities in Japan, planet Earth. There, she is found by a regular high-school student named Takaya. It appears that Foltjunia has lost her transformation abilities. Her sisters decide to stay with Takaya for a while, masquerading as high-school girls, which greatly complicates the young man's social and romantic life.

Having the same characters and initial plot as Hatsukoi Monogatari, Dennō Tenshi: Digital Ange is a Japanese-style adventure game with very limited interaction and strictly linear progression. Most screens allow the player to choose verb commands such as "Look", "Talk", "Watch", "Go", etc. from a menu, usually combining them with character and object names in a sub-menu. Typically, going through most or all options triggers the next event.