[@King Cosmos]

alright, different problems I have found. I'll go character by character here
going from fifth to first

Keita, Great character. well done and everything.

Jasmine, I only have one problem with her however, This is a huge problem I have with just her, How did she get to rank 4 at the start of the year (which hasn't taken place yet because that's where we start) this is highly unrealistic and I would love it for you to change this into her transferring during the fourth quarter of the second year then she might have had time to rank up accordingly

Touma, There aren't a lot of things that are wrong with him, heck there is NOTHING wrong him at all and he seems to be a great character but... you did say he is the tallest student from all Water dorm which restricts what I can do with Water Dorm student NPC's

Asahi, I have plenty of issues with him, for one How did he get to this rank if he doesn't challenge often. with not often I'd expect less than the average students who are fighting for the top

The academy doesn't just put you at rank 2 based purely on skill. You still have to duel your way up and prove it by beating a lot of people. Asahi can be as good as he's stated to be, but if he didn't duel very often, he'd maybe land around rank 15 to 10 rather than all the way up at 2.

okay after saying all that let me say this.
Asahi is still an awesome character and fits the Water dorm perfectly. He represents exactly how calm waters can become the most devastating storms when you least expect it.

Kanna, Alright as I went through Kanna the more I look at her the more problems I notice but as I go through them those problems became a plus considering the Water Dorm leader 

Alright the same issue as with Jasmine here, to quote what your sheet says 

"At the beginning of her third year, she finally made the call to switch to a new deck and chose Nekroz for its apparent versatility and the fact that it was still at least a Water attribute deck. With this new deck, it was like a weight had been lifted from her shoulders and she saw massive improvements to her dueling that rocketed her to the top of her dorms rankings."

I am going to say this is the biggest issue with her

The same problem as Jasmine, The RP takes place at the start of the third year, in other words, she would be using her new deck for the first few times putting her at a lower rank possibly at the same rank Asahi would be if what your sheet says is true

How did Kanna get rank 1? if Asahi is rank 2 then HOW did Kanna get past Asahi if they never dueled? Did Asahi refuse to duel her? Kanna would have been number 1 if that's the case, but Asahi's reputation would have been known as the guy who let a girl get past him without putting up a fight