The soldiers of Second Earth believe they could die at any moment therefore it is implied that soldiers often engage in casual sex with one another as a form of relief

Sexual activity can be found in episodes 2, 4, 8, 15, 17, 18, 20. Other than 15 and 20 most of the sex takes place off screen or is implied

Some sex scenes with nudity.

In the Ending credits of every episode, Marlene is seen walking in the water topless.

Bloody violence with the Blue.

Some profanity in the English dub.

Some smoking.

The scenes with the Blue can be frightening.