「Battle for unfaithful wife」as a contest among turtlehead males that continues for hours and hours. Catching a dose of the clap from her afterward is always a GAMBLE.
「Battle of the turtleheads」depicts the GAMBLE every person took when entering those divine「gateways for turtleheads」(䦰) playing the lottery with one's life as it were, remembering that as with any gambling venture, the House never loses and the shaman always gets the better of her clients, eventually. Turtles, specifically the turtle's head, is a Chinese euphemism for the penis…males battling for a prize.
「…[T]urtle males can be very aggressive with their mating. When the male mounts the female he often will try to bite her head and front legs. The male locks his feet inside the female's shell and begins copulating. At this point he flips over [on] his back…. They stay coupled for up to [three] hours. The female will often drag the male around. For many new keepers, it appears the male is being hurt. Afterwards the male walks off as if nothing happened.」
[ https://aboxturtle.com/mating.htm 2014-11-07 ]
TO DRAW LOTS since only one in many males are successful copulators:「…green turtles during mating season. …The male turtle hangs on to the front edge of the female's shell with a pair of large recurved claws. The male's tail has another 'claw' at the end. This facilitates a sturdy three-point attachment, whereby the penis can enter the cloaca of the female. Attempts to knock male #1 off of the female turtle by males #2 through 17 are frequent, severe and generally unsuccessful. Physical damage to both members of the copulating pair is common. Occasionally, a horny, excluded male will mount the pair (this is going absolutely nowhere for male #2). Further on, another male may join the fun and attach his tripod of claws to male #2. So on and so on, as a chain of turtle love and hormones extends to four or more. When this sort of thing happens with earthworms in the garden, it's merely curious. With 400 pound sea turtles it's a bizarrely orgyastical circus of ancient oceanic sexuality. Bring your camera.」
「But it gets better. Male turtles are known to hang on (and in) for hours on end. For 2, 8, 12 hours…or more. Through the years, this has been impressively noted by the males of the human species. I'm willing to bet this is somehow related to the belief that turtle eggs are aphrodisiacs beyond compare. Incidentally, and perhaps not unexpectedly, the dried and shaved green turtle penis is considered wickedly potent when added to booze, a sort of Viagra with King Kong strength. First hand experience tells me that neither are particularly effective. Back in the ocean, males are the pursuers, the females are the deciders. An unreceptive female will press rear flippers together and/or rest on the sea floor, prohibiting access to her cloaca and eggs. That leaves the males swimming in circles around her, biting each other, mounting each other, mounting logs or buoys or…(back to the warning signs on the beach)…you. A horny male green turtle will aggressively mount a swimmer, snorkeler or diver. Expect a big claw on each shoulder and a large tail around underneath. Attached to 400 pounds of reptile ready for some all day and all night lovin.' Consider yourself warned.」
[ https://deepseanews.com/2009/05/sea-turtles-get-it-on-and-on-and-on/ 2014-11-07 ]

External source definitions …excluding politically incorrect concepts and other meanings deemed offensive today; may include extended definitions, euphemisms, and mnemonics)
Japanese EDRDG: a lot, a ticket, to draw lots
Unihan extended: (non-classical) a lot; a ticket, to draw lots