The show contains many sexual references/visuals, though nothing is ever shown. Alice, the guard, is a transsexual as made evident by a bulge in her skirt and other masculine traits.
Some animated nudity in shower stalls, though nothing graphic.
Two inmate characters are clearly gay, and an entire episode revolves around their planned marriage.
A scene spanning roughly one minute in one episode shows characters being "horny", ripping off clothes (again, nothing graphic is shown) and jumping on each other. Intercourse is hinted at.
A character who appears in one episode is a voluptuous, naked woman with nothing but "X"s on her breasts.