Six months later, three billion of these monster girls were recorded. Indeed, the public called them that. Eventually the virus became inert, unless of course a monster wanted to pass on her gift.
Men and women worldwide took up jobs or hobbies 'taming' them to allow them to function. Food and water did not need to be provided, but their lust needed to be satisfied. If they were not taught to masturbate and did not get sex once a week, they would lose all ability to live like a human. When masturbating daily and getting weekly sex, monsters acted much like humans, although they had a bit of trouble with the customs. Some places had a lot of species racism against monsters, but others were accepting to 'tame' monsters. Larger cities treated monsters as normal people, allowing them to get jobs as long as they had a human or tame monster roommate or friend able to satisfy them weekly. Some monsters in shadier areas are kept and traded as sex slaves, where they are taught to be loyal by providing a drug that would make it impossible to get pleasure from masturbating or using toys, only a human could satisfy them and give them pleasure. Then pleasure is withheld until they are as loyal as dogs and will do anything their master says, and they are rewarded by being fucked like dogs.
There are many kinds of monster. Some have animal ears, tail, wings if the animal has them, and pussies. Some are like 'furries', while some are mythical creatures like mermaids or centaurs. Some are even odder, like goo girls or tentacle monsters. Sometimes monsters have a dick above their pussy, and a few monsters are just girls with a high libido and a cock. Very rarely, a man gets the virus. It either will turn him into a futa monster, or, if done personally by a monster, may produce a male monster. Sometimes they have pussies under their dicks too, sometimes not.
If two monsters fall in love, they can tame each other and live normally, with wild sex every night. However, the chaotic nature of a male monster can cause no taming to be possible, and the male monster and a normal monster (or unlucky human) will be stuck in eternal sex and orgasm. Oddly, monsters never seem to die. At the age of 100, they disappear, but they claim there is a world where monsters (and their human friends and lovers) go, where sex and nudity aren't taboo. However, they claim there are tame monster cities where they live like humans and their lives aren't focused on pleasure like those of nontame monsters. They also claim that any monster who goes in tame stays tame forever.
Monsters never seem to age, but monster children hatch from eggs as a ball of light that forms an adult monster. There are no underage monsters, and they are born knowing of sex. Children of tame monsters are tame as well, but still need sex. The species of a monster is random, and does not have to match the parent.