This is an Otome visual novel, it is a satire on highly developed industrial technology in Japan, in which the decline of human civilization, moral decays, and low birth rate gets out of control under the huge social pressure.
Someday, on her way back from work, Ruri picked up an abandoned android, Aizen. Ruri stayed up all night to repair Aizen, but due to his former hostess’ negligence of periodic inspection and maintenance, Aizen’s body function could only last for five days. So Ruri decided to spend the last five days with Aizen.

[From Steam]