Unbeknownst to the group of three guys, the "girl" they're hitting on is actually a married woman! They start by playing the King game, things escalate from there, and 4P sex begins! Airi has sex with the three young guys and drowns in pleasure.

Is homosexuality observed in animals? Is it steady orientation or occasional behavior, and which is more common?

Before anybody jumps all over me: No, I am not saying you are evil for being gay, or bashing gays in any way.
I am simply answering this question as factually as I can. This question likely came from a point that’s been circulating around the internet, that some LGBT activists have said. It’s something along the lines of “There are over 500 animal species that exhibit homosexuality, so it’s natural.” But, there are several issues with that. Statistical issues: An estimated 1–2 million animal species exist.
Hell, let’s just assume exactly 1.25 million animal species exist for the sake of argument, and that 750 of them exhibit homosexual behavior.
That would mean only 0.006% of animal species exhibit homosexual behaviors. Population issues: Of those ~750 animal species that exhibit homosexual behaviors, it could only be 0.1–10% of the total population of the species that has shown homosexual behaviors, and not be nearly a high enough percentage to be described as “common”.
The practice of those behaviors is generally an outlier.
It wouldn’t make sense to brand a species “homosexual” that has been seen committing homosexual a handful of times, despite the overwhelming majority of animals in that group that are straight. Lifestyle issues: Many of the animals who have been seen to commit “homosexuality” live very unnatural lifestyles.
Zoo animals, for example, do not live in their natural habitats, do not eat their natural diets, and are in very unnatural social groups.
That’s like if aliens saw a prison and concluded the rate of homosexuality in there was the rate of our entire species. Nurture issues: A high percentage of the animals who were observed to be “homosexual” were raised unnaturally.
Whether it be in a wildlife reserve or zoo, they could of been raised by only humans or by only 1 parent without the exposure to their normal social group. Genetic issues: If homosexuality was truly “natural” and not learned, it would have to have been inherited genetically.
It simply is not possible to keep passing down “homosexual” genes, because if you truly were “homosexual” you would not breed.
It is also possible for feminine traits to be passed down to males, but those males would breed less than others. Misunderstandings: Many people misinterpret a dog mounting another dog, or a Gorilla mounting another gorilla as their “preference” and are quick to label them “Homosexual”.
They fail to realize that many animals simply do this when they have a dispute with another animal to show dominance, and are not actually trying to mate with the animal.
Very often they will get into fights when this happens, because it’s a dominance and social thing.
Even dogs that frequently mount others will be quick to breed with a female when given the chance. Again, to reiterate: I have no issue with your sexuality, there isn’t anything I could care less about. However, I do have an issue with people trying to politicize science.