This show is completely free of any fanservice, subtle or otherwise.
None.
Violence & Gore
Mild
Brief and mild exchanges between the human main character and some hostile robots. Missiles, lasers, and bullets are exchanged during these brief conflicts. Blood and injury detail are never shown.
A character blows up after accidentally setting off a trap. The character is instantly enveloped in smoke, so the actual death and detail is never seen.
Some implied violence. Guns are drawn and explosions are seen, but no impact or gore is shown.
Profanity
Unrated
Infrequent use of 'damn' and 'hell' in the official subtitles.
Alcohol, Drugs & Smoking
Unrated
The main male character is briefly seen drinking in episode 4, and later references previous intoxication.
Frightening & Intense Scenes
Unrated
Although the show has very little action, the little action that is present is intense. These scenes also happen suddenly, so viewers may be startled by them.