I may or may not have posted asking about this on here already, but I'm pretty sure I haven't yet. It's an older one, pretty sure it's 90s era (my favorite time of artwork/animation for hentai, especially guro hentai).

It takes place on a large ship, like a freighter or a tanker or something.. not like a cruise ship, and there's a monster roaming around or a bunch of tentacles or something.. I'm pretty sure one of the girls gets controlled by the monster too, and eventually she gets crushed by a mass of tentacles at the end... there's 3 girls I believe that are the "heroines" and 2 of them die, only one survives at the end iirc.

BTW it's NOT Alien from the Darkness, or anything that takes place in space.. i'm like 99% certain it's a boat/ship, on water too. But it certainly could be one of the "darkness" movies, if there's one I can't seem to find atm..

Sound familiar to anyone?