The Manhard imprint published just under 100 titles from 1973-1979.
The style of the cover art would only change once near the end of the imprint's life. All the black ink line drawings appear to have been done by a single artist, or a pair of artists with similar styles, whose name(s) remain(s) unknown. There are also a number of covers I have been unable to locate.
Here are another dozen (or so) titles:
Sluts in the slammer stories are the sugar cookies of smut: Dependable, basic gratification. When you buy a book called Boys Behind Bars, you know what you're getting, even before the back-cover blurb spells it out: "Take one detention cell and fill it with horny boys and something is going to happen… fast! As quick as his faded uniform was stripped from his body, he was thrown face down, and held there… until every boy in the cell had it!" Except when you don't… Benjamin David's apparently formulaic adults-only pulp is something altogether stranger and more moving than you'd have any reason to expect.
Sweet-faced, 16-year-old Tod Custis, a math prodigy from Champaign, Illinois, wafts into Dorm 3-C of St. Elmo's Reformatory (named for the 3rd-century martyr associated with luminous electrical sparking) on a cloud of sleazy tabloid celebrity: The smart money says this slim, brainy newbie, convicted of killing his parents, is no match for eleven hardened delinquents aching for a piece of his famous and no-doubt cherry ass. The smart money, however, is wrong. Custis is tougher than he looks -- way tougher – along with more ruthless, disciplined, devious, sex savvy, manipulative and image conscious, which is where self-taught rocker Billy Joe Winslow, a handsome blond with violet eyes and a knack for tailoring prison rags so they show off a fellow's manly assets, comes into the picture.
Within weeks, Custis is in a position to do cushy time: He's got power, privileges and Winslow, a great lay, good time and kindred spirit. But staying isn't an option: Born into poverty, incest and abuse, Custis caught a once-in-a-lifetime break when a teacher spotted his gift for math and lost it to his degenerate biker dad, Rod. Rod caught his wife with her lover, beat them both to death and staged the crime scene to implicate Custis. Smart by nature and brutalized from birth, Custis has been plotting revenge for a long, long time, but Winslow has thrown him for a loop. Blindsided by something that seems an awful lot like love, he lays his cards on the table – he doesn't want to leave St. Elmo's without Winslow. Common sense says that small-time offender Winslow should stay put, serve his penny-ante time and walk away free and clear. But it's not about logic for him, either, so that's that.
The escape goes smoothly until their getaway car blows a tire, but fate is in a benevolent mood: A silver Mercedes materializes out of the two-lane darkness, with rich, horny, drug-addled hippie poet Yseult Homann-Potter at the wheel. She not only gives the lost boys she dubs her "lambs" a lift to Chicago, but installs them in the deluxe digs she shares with her twin brother, Tristram (how creepy is that?) and introduces them to life in the divinely decadent lane. And this is where Boys Behind Bars takes an unlikely detour, leaving the high-octane, couple-on-the-run highway for the thorny back roads of relationship work. It's going to take a whole lot of negotiating if the fairy tale romance that blossomed in the hothouse of St. Elmo's is going to survive in the real world. Who'd have seen that coming?