Vox Mentis

Well, a little paranoia never hurt anyone. You'll note that Jane said they're "aware of his behaviour', not necessarily that your assessment is completely factual. Ask whether she can give you assurance of the following, while preparing yourself for the likelihood they can't or won't give you straight answers to the following:

1. Has Smugass propositioned a member of the faculty in the same way you have?
1a. If he has, will they divulge to you what he said/suggested to them?
1ai. If they will not, is this because of Academy policy or because he explicitly told them not to?
2. Whether he has or not, and whether you are now privy to his plans or not, are you able to trust the faculty to lie to him if he does come and inquire as to your movements?
2a. Would Jane ensure, in the event Douchebuck does come knocking at her door, to impart to him the following information: that you came, complained that his methods were bullshit, and got told to suck it up and to not expect outside help?
3. If Prickstain does proposition the faculty in future to help with a scheme, and he does not explicitly swear them to secrecy, if you inquire will they tell you his plans, or, say, at least the existence of a plan?
4. (contingent on your bedroom having a lock, I don't remember) can the faculty promise to not use their skeletons keys or whatever to enter your room on his behalf?
4a. Can they promise to refuse his requests if he does ask them to do so, making up a rule like that doesn't count as "persuasion" for their purposes?

These are all general assurances so you can afford to be a bit less paranoid, spend a bit less time trying to second-guess him, and thus make the next two days more authentic. Get well-rested and visibly take full advantage of the comparative luxury this place is offering you.

Once you've made sure you've got appearances covered, go nuts. Smear vaseline on his doorhandle, take the batteries out of the tv remote, launch spitballs, prank him, gaslight him in incremental movements of his possessions if you can sneak into his room, basically take the excuse to be as juvenile as you wish. Have a screaming tantrum, pull his hair, walk in and change the channel, ignoring him, be loud and/or obnoxious in his vicinity, and really make it look like you're giving it your all.

You need to stick to the most childish methods you've got to make it seem like you're not a threat to him, and he can afford to stick to putting up passive resistance. That's the best-case scenario, but you need to be prepared for him cracking and replying in kind (at which point you're going to want sanctuary in your own room), or having something nastier planned out.