Or maybe the first generation of sex robots.
Dolphins have very muscular vaginal orifices, and can use these muscles to manipulate objects and carry them. Link
In certain dolphin species, namely Bottlenose, female vaginal tracts secrete an organic chemical while mating that allow a male to orgasm for as long as the penis remains within the vaginal tract, resulting in multiple continuous ejaculations. This is speculated to increase chances of fertilization for each act of reproduction. It has been tested and proven in controlled environments that this same organic chemical produces identical effects in similar dolphin species, and in mammals with less than sufficient genetic disparity, including primate and primate families.
Due to a combination of carbon compounds and other organically produced enzymes, the chemical maintains properties that effectively eliminate the ‘refractory period’ wherein the male penis involuntarily becomes and remains flaccid for a varying amount of time, during which ejaculation is physically impossible. It is hypothesized that a male could remain united, the penis within the vaginal tract, for potentially up to several hours at a time. While this would result in a constant state of orgasm and resulting ejaculation for the hypothesized period of several hours, it is unlikely that either the male or female would remain in this state for such an extended period of time. This would also have the negative side-effect of significantly lowering the males sperm count, due to the constant state of ejaculation, resulting in an indeterminate hiatus from successful reproduction until the sperm count of the male returned to the standard level of fertile sperm. Link
(I have no idea if this is actually true and I don’t care to confirm it. But sex bots should definitely have it.)