Project Utopia (176 chapters, translated to 106) Korean webcomic hentai, I mean ADULT THRILLER.

Purports itself to be a XXX-rated
Battle Royale, pitting kidnapped victims on a lawless island against one another in sadistic contests. Better described as a cheerfully brazen
Carry On with the decidedly un-cheerful addition of nonstop rape and murder.

Despite the avowedly slumming tone, it's not without some awareness of its well-worn genre. Unlike Battle Royale's terrifying "Game," bloodshed is strictly elective. Unlike
Lord of the Flies, all needs are catered for. Everyone could, in theory, enjoy ten months in pampered paradise, taking home 500 grand apiece. However, Creepy Boss Dude splits the victims up into smaller teams, promising
MO MONEH to the ones with the most survivors, or sometimes, for getting the island's total population below a certain quota! Also, murder someone and their 500k is yours!
RUH-ROHA serious work might've done something interesting with this laissez-faire, but our scholarly ass man (he really can draw a fine ass) has no time for that gay shit, and so savagery explodes with numbing regularity. Timid college kids, civil servants and retirees turn into slavering Go Nagai beasts and
Hokuto no Ken despots at the slightest whiff of sex or cash, with violent criminals already occupying a chunk of roster. Horror Movie Retardation™ ensures even our embattled protagonists (Nice Guy, Bad Boy and Tough Girl) are hard to root for, given scant prudence in the service of contrived peril.
Much like action stars taking brain-shattering blows, only to awaken mildly groggy at
CRIME BOSS HOUSE an hour later, nobody seems particularly scarred for being cruelly violated. Bleakly pragmatic survival adaptation, or crummy writing? I think it's 20/80. A passable if farcically contrived Hobbesian nightmare, AND Clark's win quote from KOF '98. Burly McWrasslinman might've dehumanised you utterly, but you'll be glad for his patronage when
Violence Jack bandits (AKA Jim, Patrick and Kenny from accounting) roll up, because
"Losers have no rights. That's what history is all about." 
Transparent soapy junk. 176 chapters, fucking hell. Woulda read the whole thing tbh, I have to know if Massive Thug and Creepy Loner's uneasy alliance holds, and if Bad Boy and the long-suffering Tough Girl will someday confess their feelings! She thinks he's being stolen away by the flirtatious New Girl, but little does she know - he has murderous suspicions of her and Nice Guy slamming behind his back, and even split a young motherfucker's wig with the omnipresent Convenient Rock, just for groping her while she slept! (in this universe, groping an unconscious girl is the equivalent of a shy glance at fifty paces)
Perhaps Convenient Rock is Bad Boy's Stand? Oh shit - you could call it
Lovers Rock. Or
Significant Others Stone in the English version.