High-definition, 20 meters underwater, (1man, half-octopus man with very many tentacle arms but the torso of a man and a huge cock:1.3), (floating above the seafloor in zero gravity), (1woman, a helpless and beautiful female scuba diver wearing a full-face scuba mask over her eyes and a one-piece swimsuit), (dive knife has fallen from her hand and an empty sheath is strapped to her thigh:1.1), (the monster is mounting her and impregnating her with its tentacles:1.3), (multicolored tentacles), (doggy sex position), (full-face scuba mask:1.4), (air bubbles leaving her mouth:1.3), (orgasm face:1.3), (ahegao:1.3), (double penetration), (tentacles in pussy), (tentacles in ass), (tentacles wrapped around her body:1.4), (deep underwater:1.3), (lots of fish:1), (detailed face and eyes:1.3), (facing viewer:1.3), (close-up view of face:1.2)