for family. (ᵃᵖ)

where roth is much more dramatic in his gestures to partner with jacob, pearl makes herself seem cautious when she first runs into jacob. at the time, she knows exactly who he is, but she makes it out like she doesn’t know -- other than the fact that he’s an assassin, of course.she does something that roth does, still: convincing jacob she’s against starrick.that’s the big one. that’s the turning point for jacob. that’s what makes him want to partner up with both of these people. he wants to bring down starrick and if they want to help him do that, even better.but pearl plays him and she continues to play him to keep him hooked. she comes up with deal after deal after deal and it was working. if jacob hadn’t happened to find out she was actually a templar, it’s likely that would have gone on for some time because -- let’s face it -- at the beginning of the game, jacob’s gullible.

gonna take a detour for a second to discuss jacob being gullible because that’s it’s own thing. i really think jacob, growing up, never had a reason to distrust anyone. for the first six years, he lived with his grandmother. from then on, his father as ethan trained jacob and evie. and ethan loved his children a lot. he and jacob certainly didn’t get along but that’s because ethan always told jacob and evie exactly what something was, exactly as it was. he didn’t sugarcoat anything and that led to jacob’s resentment for his father. ethan was always honest about jacob’s training and performances and methods.jacob was never lied to. not seriously, anyway. for the first twenty years of his life, everyone was brutally honest with him. and why would they start being dishonest now???jacob is gullible. when someone tells him something and they make it sound like the cold, hard truth, he’s very inclined to believe it.

so why wasn’t he cautious after pearl when partnering with roth??

for starters, yes, jacob’s shift after his interactions with pearl wasn’t incredibly noticeable. i viewed it as he became a little more selective on who he chose to align himself with. and, to be perfectly honest, jacob is a little cautious when he goes to meet roth for the first time:

“ I’ve been picking off your soldiers one by one. Doesn’t that make you angry? ”  -- he’s testing roth’s motives. but when roth doesn’t really seem to care, that tells jacob he’s a free agent so, maybe -- just maybe -- there aren’t ulterior motives.

“ What do YOU get out of all this? ”  -- he tests roth again. so far, he’s been listening to roth’s deal and he’s hearing some things he wouldn’t disagree with, of course. roth is playing to jacob’s wants but jacob is still wary. he wants to make sure roth is all in if he’s going to go for this partnership.

and, finally, roth decides to feed jacob one last time and fuel his ego:  “ [I get] The chance to have a little fun with the bravest man in London! ”  Because, on top of being gullible, jacob’s egotistical. he won’t turn down a compliment, that’s for sure. and roth certainly sounds sincere so maybe everything else he’s saying is true. right??

what roth does that’s different from pearl is he plays directly to jacob’s own personal goals.pearl told jacob she was against starrick because of competing bus companies. well, she’s against starrick, so that’s enough for him but, to be frank, he doesn’t really care about the buses.roth says directly that he wants to bring starrick down. he wants to cause trouble, he wants to intimidate some people, and he wants to cripple starrick’s control.that is exactly what jacob wants to do. like to the letter.while pearl consistently strings jacob along and makes it hard for him to resist their deals, roth puts his arm around jacob and turns himself into a kindred spirit. he makes himself into someone jacob thinks actually understands him and his methods. 

and, in truth, roth wasn’t lying. he did want to bring down starrick and he did want to cripple his control. but what he didn’t show jacob was just how far he was willing to go.you have three missions with roth in the game and each one increases in intensity as you go. the tipping point is, obviously, when they’re about to blow up one of starrick’s factories, but jacob sees children going into the building bc they work there. roth isn’t willing to stop. he’s not going to let anything get in the way of him or his plans.the second jacob defies him, jacob becomes roth’s enemy.

but if roth was genuine, how did he manipulate jacob?

he left out the fine details. he never told jacob just how much he wanted to do and how extreme he was willing to make things. he never told jacob he was willing to murder children just to make this happen.and when jacob saw that that’s what roth was willing to do, he started to wonder exactly what he’d done while working with roth previously. he wondered if their actions earlier had caused a lot more trouble than jacob had initially thought. maybe there was a whole branch of the plan jacob wasn’t aware of and roth was just using him as a pawn.this seriously fucks with him.he’s consumed with guilt and anger -- this is very apparent in the scene on the train after jacob assassinates roth, when jacob and evie have their argument.

not to mention, when roth is dying, he literally grabs jacob by the face and forcefully kisses him. first and foremost, that’s sexual harassment. and, yes, i know, jacob is canonically bisexual but that doesn’t make any of that okay. jacob physically looks disgusted after roth kisses him, so, bi or not, that was also something that messed with his head.