At one point there is a naked but formless body of a girl in the sky. In one episode lain explains to Alice that she loves her. It was an awkward scene so hard to tell if it was friendship, platonic or something more.

Prostitution is implied on a couple of occasions, but no acts are seen and even skin is surprisingly limited.

At one point in the series, a mailman made advances on a woman but she rebuffed him. For context the man made flirtatious remarks, and she teased him about being a bored and lonely housewife before closing the door.

A girl catches another girl implicitly masturbating, the act isn't actually seen at all, it is rather implied by the other girl. A few people kiss.

A man looks at a woman, sitting in his office, who is crossing and uncrossing her legs. (brief)

A train is abruptly stopped and and an announcer comes on saying that there's been an accident, you hear someone on the train question if they hit someone, you then see blood dripping from a wire that the train is running on, later in the episode you see a vision of the train hitting a young girl (off screen, No Blood)

Bits of blood hit a person's face after someone unwillingly shoots himself offscreen.

A dead woman is seen face-down with a pool of blood around her head for a few seconds.

A few uses of Shit, Hell, and Damn.

There is a very high tech fictional drug called "Accela" that many people take(including young teenagers who you see the drug getting sold to when it's first referenced) in a club called "Cyberia" where they play loud techno rave music, The drug is also likely supposed to be a reference to the real life drug "Ecstasy" which was very popular and predominantly used in the underground rave scene

Adult men and women are shown taking swigs of what appears to be beer at a club. Nothing a kid wouldn't see at a pub.

As a whole, this anime is extremely surreal, suspenseful and intense, favoring a foreboding atmosphere, extraordinarily bizarre imagery, and lots of very deep and incredibly confusing themes (mainly the impact of the internet on a person's life) to create a lot of unease and tension, which might be a bit too much for some.

Two men are briefly shown yelling in pain from an unseen cause. A seemingly possessed and monstrous-looking girl chases two males, briefly attacking one offscreen. Her face is shown again as she opens her mouth in stop-motion.

The series is not overly violent and it has little blood for the most part, but certain scenes can be eerie or unsettling.