Embryon
The people of Embryon and their relationship with Roland.
Serph
As Serph is you, his reactions to Roland depends in great part on your opinion of the man. However, in the script of the game, Serph seems to share Gale's opinion of Roland when they first meet, but nonetheless decides to do as Roland asks. When he wants to join the Embryon, Serph lets him, probably in part because of Gale's advices. I think Serph sees Roland as another member of his team who just happens to have his hair and eyes in non-matching colours.
Gale
Right off the bat, Gale does not like Roland. He has always been very blunt and matter-of-factly with everyone, but as Roland tries to weave a poetic half-truth to the Embryon, he gets rather irritated, because he sees right through the manipulation. He calls Roland on it, going so far as telling the man he has no honour and that if they are the people of the land they nearly gave their life to reach, then Lupa died in vain. He still follows Serph when his leader "tells" him they'll do as asked, but as he says himself, "not for your sake, but Sera's, and Fred's". He strongly recommends the Lokapala take good care of Cielo before he leaves.
Things mellow out when Roland joins the Embryon, as Gale tells Serph they can trust Roland because he sees the man has honour in his eyes. Later on, he says he admires Roland's courage in taking the virus willingly while knowing the risks involved. All in all, after a rocky start, Roland and Gale seem to be getting along all right. Although if they didn't, Roland would probably be dead, so it'd be kind of a moot point.
Argilla
At first, Argilla doesn't seem to like Roland much at all, who sees her as a machine. She is outraged by Roland's telling them the Cyber Shaman created them and then discarded them like they were nothing, and came very close to ripping Roland's head off before Gale stopped her. Even when he joins the Embryon, she still doesn't trust him, even if she goes along with Serph and Gale's decision to let him join.
By the Power Plant, though, she seems to have warmed up to him, even whistling when he manages to open the security doors and exchanging a bit of banter with him, which makes him smile. At the end of the dungeon, she decides to stay behind to help—read save—him. Unfortunately, when she gets to him, Meganada is already chewing on his unconscious body. Enraged to be losing another comrade she cared deeply about, she screams her head off at the huge monster as she rushes in to attack it. Her assault fails, but it allows Roland to complete his plan, and, after exchanging a smile, they die together.
Cielo
There is not a whole lot of interaction between Cielo and Roland, beyond when he was captured, and that all happened off-screen. When they bring Cielo back to the Embryon, he doesn't seem to have suffered much, though. Cielo seems to feel a bit for Roland, mentioning later that when they (Roland, Adil, Fred and himself) were catching up with the other, Roland was having a hard time eating; he was throwing up and gagging all the time. He then mentions then at one point, they were all like that too. He knows it's hard, but he seems to appreciate Roland's effort to get in synch and on the road with the Embryon.
Heat
Roland pretty much sees Heat twice in his life.
The first time, he stays very far not to get caught between a murderous Heat and Serph.
The second time, he stands out of the way as Heat sticks his arm through Serph and falls in the EGG with him.
All in all, the only time they interact at all is on the Sun, if you did all the right things to get Heat in your final party. Roland encourages Heat to go rejoin the Embryon, telling him "this is something you have to do," before gently shoving him towards Seraph. In a way, he steps out of Heat's way so the original Embryon tribe can finally be reunited.
Sera
While Roland does not like the Cyber Shaman, he needs her power to change things. However, one can wonder if "the Cyber Shaman" and "Sera" are one and the same in his mind: he has a small clip of Sera in the EGG on the disc his mole sent in, but he doesn't seem to know she is basically a small girl in a big body, doing what the grown-ups are telling or forcing her to do.
Sadly, they don't interact at all, since Sera faints nearly as soon as she is rescued from the EGG and only wakes up after Roland leaves the party. She however must not have hated him, since he's around with everyone else when she, as Seraph, arrives on the Sun.
Seraph
I will have more to say about this once I reach the Sun and get Roland in my party. I hope. I can speculate though that Roland probably had a WTF moment when he saw Seraph. It's not every day that an AI and a psychic girl suddenly merge into a complete, enlightenment being after death while you're around to witness it.