The main larger plot will be investigating the ruins of the Animist's lab and trying to understand the properties of the Ani-Virus. The virus presents a major threat to human society and the Earth's ecosystem, so escaping without a cure for it would be criminally irresponsible. (and increase the random encounter rate by 300% :))
That said, you will have a decent chance to escape and/or overthrow rebirth if you really try, although fighting rebirth will require quite a bit of power.
The Ani-Virus and Transformations
When you create your character, you should note what strain of the Ani-Virus you have, for example, one might have a version of the virus that causes lupine features, or a virus that causes hermaphrodite features. Whenever you infect someone with the virus, you may change that person according to the strain you have, and may also manifest the mutation of your strain according to the level of mutation you are experiencing. After infecting the same person twice, a genetic exchange occurs, and that person becomes immune to your strain of the Ani-Virus (at least for a while) and you acquire a new strain of the virus. (which need not be the same strain as the person you infected twice.)
A character can have up to 3 strains present in their system at a time, or 4 strains if they are currently under the effects of a level 3 transformation or humiliation.
The Transformation/Humiliation Track:
1. Level 0
2. Level 1
3. Level 2
(go back to 1)
A winning streak of 3 wins or losses (counting fights only) upgrades a person's transformation to level 3, regardless of where they are on the mutation track.
The Ani-Serum will also now be available for purchase, and grant incredible power in combat, in exchange for increasing the severity of mutations experienced. Minor versions of the ani serum (the anthro and futa injections) increase the severity of a mutation experienced at the end of combat by 1, while major versions of the ani serum (the analyst and berserker injections) cause an automatic level 3 mutation, although the power they grant is staggering.
When a fighter loses a fight, he does not automatically risk becoming a pet. However, he does go 100 credits into debt, which can be forgiven by doing a service for the fighter who beat him (such as having sex or participating in a fight and handing over the winnings, both of which give the fighter 100 credits.)
Another way a fighter can pay his debt, if he lacks credits, is to have himself collared by Rebirth. The fighter agrees to wear a collar, in exchange for allowing Rebirth to sell the rights to use the collar to harm and control him. There are three main types of collar contract:
Standard Collar: When activated by the purchaser, it makes the victim horny.
Power Collar: When activated by the purchaser, it delivers a firm electric shock to the victim.
Submission Collar: When activated by the purchaser, it crushes the victim's mind, making the exercise of free will difficult.
A standard collar contract is worth 50 credits, a power collar contract is worth 75 credits, and a submission collar contract is worth 150 credits. A fighter may have up to 10 collar contracts, but only 3 unsold contracts at a time. By purchasing a fighter's collar contracts, another fighter can easily blackmail the fighter, by threatening to activate the collar contracts during a fight, or simply using them to beat the character into submission. Collar contracts are freely transferable, for any agreement that both parties find acceptable.
Pet is not a term used by rebirth, but collared individuals who are owned by another are often referred to as such. Fighters should carefully weight the value of acquiring needed equipment against the risk of becoming a pet by mortgaging their own free will. A fighter may get out of a collar contract by purchasing the contract himself, although he may only do this at market value if the contract is unsold.