Eduardo Saverin is sometimes a monumental asshole and he doesn't realize it or chooses to ignore it. This is one of the first things Mark realizes about Eduardo; it's also the first flaw that Mark allows him, because the thing about Mark is that people think he's a robot.txtapable of feeling when in actuality he pays more attention than most people do. It just manifests in subtler ways than people are used to, because Mark never really talks about the things he pays attention to.
He knows Eduardo's favorite color, his coffee order, his class schedule, his preferred brand of shirt, his tones of voice, his different smiles - and so on. If asked, Eduardo would say he knows those things about Mark and he would, in a superficial way. He would say something like Mark prefers hoodies because he thinks putting effort into your appearance is foolish, which is partially true. It's not the full truth, though, and Mark knows that Eduardo hasn't picked up on the part about honesty. He doesn't realize that Mark prizes honesty above everything else, which is why he tries to be honest about people.
There isn't a single person without flaws. Sometimes flaws are unforgivable: like intolerance of different religious beliefs. Sometimes flaws are annoying: like a tendency to suddenly (and randomly) interject with song. Sometimes flaws are wrapped up in a person's personality: like Eduardo's inability to recognize he's an asshole.
Mark lets everyone he considers a friend have three major flaws, because it's unreasonable to hold people to impossibly high standards. Eduardo's are his constant Nice Guy act, his preoccupation with image, and his very low-key disdain for America. They're all things that Mark considers integral to Eduardo being Eduardo, so he never brings any of them up. They also don't pose much of a problem on a day-to-day basis, so they're easy enough to ignore until Sean Parker comes along and stirs up all three.
In general, Mark is pretty good at predicting people's behavior. He knows that Eduardo isn't going to like Sean from the moment they get the meeting, because Eduardo thinks Sean's a loser. It's a different kind of thinking he's a loser than when Eduardo says that Dustin is a loser or that Mark is a loser, because Eduardo does that affectionately and without malice. He thinks that Mark and Dustin are going to ascend higher than what they are currently. In Eduardo's view, though, Sean has nothing to achieve. He's already fallen and he won't get back up.
Sean isn't good for their image, and Eduardo resents that Mark doesn't care about their image. This is where Eduardo's preoccupation with image sort of conflicts with Mark's insistence on honesty. Mark thinks that a person's image should be honest, and Eduardo thinks that a person's image should be perfect. Sean would be a black mark on their image, so he's no good for them. Besides, Sean is only using them. He represent the scum of America, and just.
There was no way that Eduardo and Sean were going to get along without help. Mark just wasn't expecting it to go quite as badly as it did.
It's possible that Mark forgot to factor in Eduardo's occasional inability to listen to reason once he's made up his mind. Even though Sean is making sense, Eduardo's not listening to him because Sean isn't worth his time. Eduardo says that Mark is starstruck, and Mark kind of wants to punch Eduardo and pull his head out of his ass.
Yes, Sean is glib. Yes, Mark listened and clung to his every word. That was what Sean needed, though, so Mark gave it to him. It's the kind of lying that Eduardo does all the time, but Mark finds it too much effort for his tastes most of the time. To be honest, Mark finds it kind of insulting that Eduardo hasn't figured out that Mark's as good at acting as Eduardo is. He's just not as good at consistently performing as Eduardo is, which is why he and Erica fell apart.
Most of the time, Mark tries to give people what they need or what they want. It's tiring, though, and lying leaves a bad taste in his mouth. So people eventually get tired of what they think is Mark not trying enough. Mark not caring enough. He thinks most people spend so much time being other versions of themselves, lying to themselves, that they think everything honest is cruel. Honesty is cruel, maybe, in a world where how well you lie determines everything.
It doesn't mean that blatantly ignoring a person's side of the story is a good thing. Eduardo doesn't listen, though. He doesn't listen when Mark says please come to California. He doesn't listen when Mark calls him and asks if he'll visit. His head is so far up his ass that he thinks Mark is betraying him when Mark is desperately trying to get him to stay. In that way, Eduardo betrays Mark first. He said I'm here for you and didn't mean it, not in the end when it mattered most. Mark meant I need you.
For all Sean's faults揺e has too many that Mark doesn't ignore, but the three Mark chooses to keep quiet about are Sean's extreme paranoia, his tendency to party hard, and the fact that he keeps lying about inventing Napster揺e's at least there in California and mostly willing to get Mark what he needs. Mark is aware that Sean is using him to get something, but he doesn't much care. Most people, aware or not, use other people to get something. If it was really malicious, Mark wouldn't put up with it. Sean just wants another fifteen minutes of fame, though, and that's nothing harmful.
Weighing Sean's faults against the benefits, Mark finds that it all evens out. Sean makes sure that no one in the house starves, he makes sure that they sleep sometimes, and he takes care of them. It's not necessarily as good as when Eduardo (or Chris) does it, because Sean orders things like pizza and Chinese and doesn't care about the nutritional value of what he feeds them, but he's nowhere near as bad as Eduardo thinks. Most of the food in the house was purchased by Sean, because they're all a little strapped for cash. He buys them beer and drugs too, but doesn't force anyone to consume them. People make choices.
When Eduardo comes to California, Mark briefly considers not going to pick him up. It would make Eduardo mad, though, which defeats the purpose of bringing him and would be unspeakably petty. Mark tries not to be petty anymore, because the last time he was drunk, angry, stupid, and blogging did not end well. Instead, he gets Dustin to drive him and they pick Eduardo up without a hitch. It . . . It still doesn't go smoothly, though.
Not that Mark expects anything involving Eduardo and Sean to go smoothly. Eduardo's mad about the drugs and the girls and he pins it all on Sean, even though they're all a little at fault and he just doesn't want to admit that. Mark takes him aside, pulls him into the hallway, and tries to get Eduardo to listen. Tries to salvage what they have.
"Wardo," Mark says, "it's not just Sean's fault and you know it. You just don't want to admit it."
Eduardo paces, which means he's upset and he's picking his words carefully. Mark waits. He wishes he had a red vine to fiddle with, but he suspects it would make him seem like he's not paying attention. Eduardo hasn't figured out yet that Mark fiddles with things as a way to focus. He thinks it's a distraction.
"Those girls probably weren't even legal," Eduardo hisses, "Mark, he's no good."
"He reminds us to eat and sleep and have fun and none of us are dead or in jail yet," Mark says, "Look. I. I know you don't like him. I know you think he's bad for our image and a prime example of what's wrong with America, but listen to me, Wardo: he's not that bad."
The problem with Eduardo is that Mark can never tell when he's actually listened to what someone's said to him and when he's disregarding it because he doesn't like what's being said. Eduardo is still pacing, and Mark is still waiting. The seconds tick by, and Eduardo doesn't say anything. Mark catches his wrist, stopping his pacing.
"I want— need you out here. Please don't tell him I said that."
Something in Eduardo loosens up, just a little, and Mark's fingers curl around Eduardo's wrist a little tighter. It feels like the first time that Eduardo's realized, maybe, that Mark means what he's saying. The words aren't as careless as Eduardo thinks, because Mark is nowhere near as careless as Eduardo thinks.
"I," Eduardo pauses, and then swallows, "I'm here for you."
He wants to mean it, even if he doesn't quite, and that's enough for Mark. Letting go of Eduardo's wrist, Mark smiles. Maybe Eduardo hasn't listened, and maybe this very beginning of a fragile peace will go to shit, but if Eduardo is at least willing to try then Mark will take what he can get.
"I should apologize," Eduardo says, a little like the words leave a bad taste in his mouth, "to Sean."
"And you should stay," Mark adds, because he's not going to congratulate Eduardo for finally getting his head out of his ass, "because I need my CFO."
There's a pause, Eduardo just looking at Mark for a long moment, before Eduardo bumps their shoulders together.
"Yeah," he says, "you do."
It sounds a little awed, like Eduardo's finally realized that Mark isn't just saying that he needs him to say it, and Mark smiles. Maybe everything will be alright.