v1.1 Update - Added more information on battling.
Since I can't find an RP group on FA I'll transplant some of the shit from there onto here and maybe we can have some fun. The rules went kinda long and are probably incomplete so I apologize up front.
So basically this is the PokeCombat Academy, a high class learning institution, in this case high school. It specializes in the arts, sciences, and of course considering this is Pokemon, battling. Battling is the big sport in the Pokemorph world so a lot of people take it very seriously as a career. The campus is large with all the facilities you'd expect at a high dollar private school including dormitories for the out of town kiddies. It is located in Kanto, thus all Pokemon native to Kanto commute. Those in Johto, Sinnoh, and Hoenn must reside in a gender assigned dormitory. If your Pokemorph is native to more than one region (e.g. Pikachu) then you can pick whichever region you want. Students 16 years and older can have a car.
Since this involves highschoolers in highschool and they're furries one can expect loads of drama. It is the glue that ties the RP together and thus to get it wound up fast and furious you should probably make two characters. Sex partners, friends, enemies, random blokes, it doesn't matter.
All Pokemorphs (or "mons" for short) can only use the movesets they come with in the game. For example you can't have a Kadabra using high jump kick. Furthermore they can only use four per "battle", but whatever four out of the move pool they use is entirely up to you and can change from battle to battle. There are certain stipulations for how to customize your mon for further battling goodness. I personally have chosen the simplified "elective course" route. You choose an elective class your character takes and they get certain bonuses depending on what it is:
Techniques: This course teaches your mon additional moves and lets you choose anything from the breeding/TM move pool of the Pokemon you chose.
Nutrition: A very boring class but your mon learns how to eat right, increasing "stats" and basically making your mon stronger and more resilient in a non-numerically assigned fashion.
(Kick)Boxing: The gentlemen's sport increases your mon's ability to fight with their hands and feet. Where as things like jump kick and comet punch are super powered and energy assisted, all mons can duke it out in a rousing match of fistibops regardless of type and training. This can be particularly useful for mons who rely on special attacks as they'll be able to throw a mean right cross when the going gets tough.
A.P. History: No one can pass A.P. History without some help. Depending on your character this class either increases teamwork and bonding (useful in relationships) or by bullying the nerds into doing your homework you start to intimidate the weak.
Battle Training: This is basically sparring and practice for the real thing. No unnecessary attention to detail, just raw get in the ring and work it out. Great for building up familiarity with the rules and working on strategies, it also helps you get acquainted with a wide variety of opponents. Taking this class helps increase the damage against those annoying "not very effective..." opponents.
Battling is a major part of the school and thus a major part of the student's lives. Basically there are two (okay I simplified to two) leagues inside the school; team and independent. Teams have a captain and are made up of at least 6 members, each of which is hand picked and can be rotated out for other members depending on the battle. The independent league is pretty much the overall pool of contestants. Anyone who is not in a team and still wants to compete joins the independent league. Generally speaking this consists of one-on-one battles with occasional pick up groups depending on the rules of the match. People in the independent league are usually looked down on as most of the better athletes are picked by teams. This waters it down to a bunch of misfits and losers. It does have a fierce reputation though as every competitor that is too outlandish, headstrong, violent, or too frequently breaks the rules is usually dropped from their team and starts up again in the independent.
Some arena battle experience is required of all students at the PCA in one form or another in order to graduate. Freshmen are given a volunteer senior or staff member as their surrogate team captain (called their "trainer") and compete against teams and individuals of their own age. All matches are set up according to the win/loss ratio, talent, team membership, and age. This is to help avoid new members getting steamrolled and to help build experience. High ranking teams eventually are eligible to compete in regional championships. More athletic scholarships have been awarded to PCA students than any other school in the quad-region area.
This is highschool, thus you can't be playing as a 23 year old. You have to pick a year and a realistic age (no going beyond 18-19 for seniors). The characters you make can join the Academy at any year but there are benefits for starting out as a 14 year old Freshmen; your elective courses roll over. So if you pick Battle Training for your Freshmen year you'll have Battle Training and whatever else you pick in Sophomore. Freshmen are a bit weaker and usually aren't fully evolved (e.g. you won't find a Charizard as a Freshman).
This brings me to Evolution and Legendaries. Basically there is no differentiation between a legendary mon and a normal one, the abilities and rarity of all mons are about equal. A Mewtwo walking the halls is perfectly normal and there's probably about 3 other Mewtwos in his classes. Evolution can happen any time and any where. Like in the games it happens in a few seconds but isn't cancelable by the mons themselves. Everstones can be purchased though and used to prevent it from happening.
Battling is pretty straight forward; wail on the other dude within the arena till one of you feints. Pokemorphs have evolved a survival instinct that when they're severely injured their bodies shut down all non-vital processes, allowing them to heal much faster than normal. Items like Potions can tap into these healing abilities while still conscious. As stated earlier each mon can only use 4 attacks from their movepool per match in addition to normal fighting techniques. Moves like thunder fang and such can be substituted for thunder punch if it suits your fancy but the biting and scratching moves do still exist and still count against the 4 move total if you use them in conjunction with their punching equivalents.
RPing rules are par for the course. No controlling other people's characters, no deus ex machina, no killing people without permission unless they're your own characters, and no blowing up the school etc. (that is unless the plot of the story involves a reenactment of Columbine in which case school detonation may be valid). Basically try to be adult about it and don't fuck with people and we'll all have a dandy time. I will moderate the RP but can assign other people to moderate as well. I'll be sure to announce any rule changes/moderation grants etc.