• cecil so rarely utilizes any of the power he's been given that even donald, his closest confidant, doesn't know about it. he's aware that something's up—he knows about the teeth, after all—but is relatively clueless as to the true nature of it. and when cecil does use it, he's careful to temper it and keep it subtle, plausibly dismissed as something he could be pulling off with GDA tech rather than supernatural ability
• because he exercises so much restraint over this, he doesn't really know what it does to him when he doesn't - basically, the greater the power he indulges, the more demonic he appears (only in the moment, so long as he's tapping into it... the effect is not permanent). inducing a little psychic disorientation in someone to coerce them into signing a contract, for instance, only has the effect of briefly causing his eyes to glow. if he has to go further and fuck with their perception of reality, maybe he'll have claws for a few minutes, too. a little mindreading, perhaps both. and so on and so forth (i have not thought on what he would look like if he snapped and let loose, simply because i do not think he ever would)
• that said, some things are just involuntary (and open secrets) at all times. his teeth, of course, are the most obvious, even if he can keep them relatively hidden... the man just talks a lot LOL and they make for a good way to intimidate people without having to get his hands dirty, so to speak. occasionally a proper growl will slip into his voice, because he can't exactly plug the well from which he accesses his demonic abilities, and so its influence is always present. his body is marked with the sigil of his mephistopheles, raised from his skin like a scar (rather than inked like a tattoo), something he's so far managed to keep hidden from everyone else since [1] he's always suited around other people and [2] doesn't exactly have a private life. again, donald's the only one who's come the closest to seeing it but only because he occasionally interrupts him in his goo bath when he has to relay something important :)
• similarly, cecil is mostly unaware that the more he taps into his power, the harder it is to resist the temptation to keep using it. using it more, and using more of it each time, can easily lead to lesser men spiraling into megalomania, into destroying themselves or turning themselves into monsters. cecil, like other faustian bargainers, isn't supposed to wholly enjoy this privilege of having access to such otherworldly knowledge and abilities, but unluckily for his benefactor, he is an exceedingly resolute person and would probably be the last to ever give into this temptation anyway. the devil will have to wait until he kicks it before he can have his prize, and no sooner
• on that note: teleportation is NOT one of the powers he was given because this man should still be forced to spend comical amounts of money to get from point A to point B if he won't get into a car like the rest of us LMFAO
• cecil did not intentionally summon the father of lies - he did indeed mean to summon a devil, but not the devil. i just think his soul is So Enticing that the head honcho would've called dibs on it as soon as he caught wind it was up for grabs lol
• since summoning a demon at all sort of begs the question of religion: no, i don't really peg cecil for a religious type. at the same time, it's hard for me to put my finger on whether he was ever religious. i just think that, as a career GDA guy, he's more than aware that there are supernatural forces out there which could potentially serve him, and now that he's director, he has convenient access to the materials needed to summon them and ample justification to do so. in short: no-one would question him if he tried.
• cecil's soul is forfeit when he dies, rather than after a set number of years or when a specific condition is met. he lives in a universe being squeezed by entropy at all times, occupying a position more likely than any other to get him killed, so a time limit would've only been redundant, and both parties knew this. and he was never going to sign off on anything that could terminate their agreement any sooner than his death, anyway
• incidentally, i like to think this created some incentive for cecil to pay a little more attention to his safety, at least on a subconscious level. maybe not manically so—like there's no obsession with eternal life here or anything—but i also don't think he's particularly concerned with his own self-preservation otherwise. the threat of losing his stewardship and the power he's acquired to effectuate it, knowing his fate is ultimately going to be to burn in hell for it, might cause him to care just a little more than literally not at all lmao
• (as an aside: darkblood admonishes cecil to his face with an angry "i'd say i'd see you in hell, but there's a worse place waiting for you!" right before being excised and, predictably, cecil doesn't react. while he may not have made any actual faustian bargains in canon, it tickles me that he probably already knows where he's going when he meets his end ahaa)
things i have yet to settle on:
• the devil will sometimes "check in" on his project, but these meetings are so infrequent that cecil can count on one hand how many times they've occurred since the start of the deal. i imagine these to be brief, dry, and humorless—if only because he won't reciprocate or entertain his benefactor for long. but even if the devil makes no further demands of him, i also can't imagine he wouldn't make him pay some form of due during each of these meets - maybe not any conventional form of sacrifice (i think this is cheesy and far too ostentatious for either of them), but what then? my mind goes to something nsfw, but... i don't know, i want to consider other things, first...
• the catalyst incident - this has to be something that nearly repeats his experience with the Order of the Freeing Fist (or does, but worse). it was such a pivotal moment in his life that it only makes sense that it's still his biggest pain point, so i imagine hitting him here could be one of the few things that could actually crack him like an egg. maybe something involving The Order proper? some mass casualty event with an insane, unfathomable body count he quickly realizes after the fact he was well within his power to prevent, especially as director (a la Guarding the Globe)? since i want the deal to happen in his younger years, when he's still relatively new to the position, it's possible he wouldn't have yet realized just how many resources he has at his immediate disposal, and thus wasn't proactive enough in preventing so much death?
• whether donald should eventually discover his secret... like the full scope of it, i mean. i don't really want this to be the case, because i like how seamlessly i can integrate a demonic cecil into show canon (for the most part), but there's so much potential for drama here that holy fuck maybe he should. donald confronting cecil about his robocop existence was already so fucking good that maybe i'd like to try my hand at recreating the same tension with this ahghghghgh