My P.C. time has really really sucked for the last couple of days so I havent really had time to play out a lot of the RP i wanted too actually in game... but! heres how I think it shouldve went down...
basically Rin had an encounter with an entity, the thing gave him a sword and regenerative powers, among other things. When he's the normal Rin, he has no recolection of, nor does he remember what he does when he's the other Rin. The other Rin is conciously aware of everything that both "Rins" do, the "Other-Rin" isnt really "evil" per-say...Just he has an agenda of his own that has yet to be revealed. There was a reason he chose "Normal-Rin" to join with...
Anyone and everyone is fine and open to post. Have fun

((end OOC))
The Nurse hadnt been much help. She said that she couldn't find anything physically wrong with him, and that she would give him some antibiotics to try to combat the "abnormality."
"Now Mr. Dashess, I want you to take two of these every day, one at breakfast one at dinner, eat first and drink plenty of fluids."
"BuT I dOnT nEeD..." she cut him off
"And come back in in one week to let me check on your progress."
"YeS, mA'aM."
Rin rose off the rather comfy hospital bed and as quickly as possible exited the infirmary wing, literally one second later he was at quad 6...
Looking around for a second he dumped the bottle of pills into the trash and was about to head through the door of the dorm when
*Wham!" Krazy Katana had bolted out of the room hitting Rin squarely in the face with the doors peep hole.
"Ha! Sorry Rin... cant chat gotta go!" Katana called as he bounded down the hall and over the school walls...
Dazed and throbbing, Rin decided hed lay down for a while. He stumbled over to the couch and fell out immediately into a deep sleep...
RiN... wAkE uP... ThErE iS nO tImE fOr SleEp... It'S oUr TuRn...
A figure was walking down the hall, emanating a sublte strange green glow from his head, a sword in his right hand, a piece of paper in the other.
The boy broke out in a run, straight for the school gate. Students and nuns alike turned just in time to see the boy raise his sword.
They didnt see the two swings he had made, but suddenly the gate crashed open, and the boy exited...
Rin awoke on the couch, refreshed and ready for the day. He got up, took a shower, put on his SJS uniform, and decided to take a patrol thru the city. He opened up the door, and right outside was a mob of students and nuns...
"Um... HeY gUyS... eRr... WhAtS uP?"