WARNING: Psychological triggers ahead, mentions of rape ahead, mentions of sex, sex organs, torture, scat and urine ahead. Please don't read if it bothers you.
More about Mr. Tagame's works.
The main character's submission to his master/owner/pimp as a sex slave/whore is shown in various ways: usually nipple piercing, tattooing on stomach, or branding on ass. Usually, the nipples are pierced to show they are owned by someone. (Arena, Pride, Genryu), in more extreme situations, the main character's cock gets pierced, (Arena, Jujutsu Instructor, The Demon Who Lives in the Castle Keep, Shirogane no Hana) and/ or even tattooed. (Shirogane no Hana). Where the character's cock gets pierced they were particularly stubborn. If they were really really stubborn, they had their nose pierced too (Eclosion, Naburimono)
If the master/owner/pimp is not possessive, then he loans out the sex slave/whore to be used by others. (Pride, Father And Son in Hell, Shirogane no Hana) Sometimes the master/owner/pimp gets bored and releases the slave/whore to become common property (Army of Fallen Tears), or common property is used as a punishment (Unpatriotic) If the master/owner/pimp is possessive, the slave/whore stays with them for the rest of his life (Genryu, The Demon Who Lives in the Castle Keep). Sometimes, they were used by others before and then become the exclusive slave/whore of one master/owner/pimp (Jujutsu Instructor, The Demon Who Lives in the Castle Keep),and sometimes they were one person's whore only. (Gamefowl Enveloped in Despair, Genryu)
I'm distinguishing slave, whore and slut since they seem to carry different connotations. Slave is BDSM slave, and in GT's works they do things like get tied up, whipped, get large objects shoved up their ass, and eat and drink non-sexual bodily fluids. (you can figure that out) They also service sexual needs (whether one person or many people) for free.
Whore is where the character gets money for having sex (with one person or many people), which seems to be rarer (Gamefowl Enveloped in Darkness, Endless Game, Genryu, Shirogane no Hana).
And finally, slut is--and this is a personal definition and not the general definition of slut, which connotes many partners---how the character responds to sex--if they are receptive, if they are moan, if their eyes get hazy. This can be with one person or with many people. This isn't something to be ashamed of, and the freest, healthiest characters give into their pleasure easily rather than resist. It is more problematic when the characters play slut (Genryu, Shirogane no Hana, Father And Son in Hell) when they're actually hating it. This applies when the master/owner/pimp tells the slave/whore to say something or act a certain way to make people laugh or so the slave/whore seems more appealing, and it usually comes off as excessive or trashy. However, Father And Son In Hell has examples where the arousal is real and occurs in the most bizarre and taboo situations, and where their body is actually saying they enjoy it. In most of GT's works, real arousal occurs.
If the situation is intolerable, the character may or may not escape. Usually where ultra-extreme torture or brutality is combined with sex, the characters escape (Father and Son in Hell, What's Inside the Chest, Naburimono, Missing, Shirogane no Hana). Where the sex itself is the intolerable situation, the character may escape (Gamefowl Enveloped in Despair). Sometimes the torture continues until the character submits to sex, but they are still confined (Trophy), and so sex is preferable to torture. Some have accepted and enjoy prostitution (Endless Game) or are prostitutes and have one true love (The Confession). One starts as a personal whore and becomes a personal slave (Genryu). Some are willing masochists and get loaned out to others, which they learn to accept or they have already accepted (The Masochist, Pride)
That gets us into alienation. For the characters who escape, then what do they do? There may be a sense of alienation when the characters escape, that things don't return to normal and in extreme cases, they can no longer be part of society. Other times it's a psychological transformation, that the torment causes them to reach some kind of epiphany, about either themselves or the world.
Father and Son in Hell- The father seems to have treated this as an ordeal to survive and now out of it, can move on with his life. The son, however, and let me know if my interpretation is wrong, it seems to me that the son is ambivalent towards the village rebellion that saved them, that the villagers have taken on the role of their tormenters and because he's gone through hell himself he understands that.
Naburimono - The main character suicides with his lover--I'm not sure if it's because of the dehumanization he went through or because his lover is male or because if his lover is a yakuza, so not sure about that one.
Shirogane no Hana - When Ginjiro escapes he has nowhere to go and no one will even sleep with him. There's this sad, empty rootlessness, and not the willing kind, but this sense of displacement, like he no longer belongs on earth.
Gamefowl Enveloped in Darkness - Things may or may not have returned to normal for Shuiichi. We last see him sullen and silent.
What's Inside the Chest - The main character escapes, but the question is what happens to him now. He goes with an old man, but will he be crueler than his last one?
Missing - The main character is not shown back to his old life. There's uncertainty as to what happens to him now.
Genryu - He is able to leave because his three-year contract to the yakuza boss is up, so he stops whoring himself to him. But-- you know how in hentai blackmail is a common theme? The yakuza boss goes through with it and releases video of the sex to the internet, which ruins the main character's life-his wife leaves him, and he's completely ostracized. Rather than committing suicide, he willingly becomes the sex slave of the yakuza boss. At least this boss isn't as cruel as some of the others. He isn't even shown eating shit (hooray!!). There is shit-eating in most of GT's stories (Jujitsu Instructor, Shirogane no Hana (SO MUCH SHIT ;____; Son in Hell, too many to count.)
Arena - He doesn't physically escape, but he seems to have escaped from his mind. His body can enjoy unlimited pleasure from getting fucked in the Arena. He is a slutty sex pig, who knows, maybe it was his secret dream like the other masochists in GT's stories. Well, we can only hope.
Byebye for now.