Great. If my life was less chaotic I'd start harassing my way into that game, haha. I don't know Pathfinder too well, so I gotta ask: Any maneuvers or specific combat styles, feats, or anything else that would help with a Dark Souls-ish style? Almost sounds like something someone would bust open the Chainmail books for.

Well currently this guy is just a character concept :V But, hmmm... Well I don't have much experience in that kind of play in Pathfinder, since I much prefer ranged and smashy tank-types, but...

Basically you want to have your Acrobatics constantly maxed. For rogues it's a class skill, so hey. You can use it to circumvent enemy AoOs for movement, allowing you to safely get in position for flanking. Which, again, as a rogue, means sneak attack damage which basically equates to backstabs in DS. Basically if you want to play DS in Pathfinder you HAVE to be a Rogue. Dex is your main stat, strength second. As for feats, anything that boosts your Acrobatics is nice, Take it as a skill focus. Take any feat that allows you to get the most out of your high Dex, too. Carry potions of CW since it's pretty much Estus. Maybe get a Summoner friend to imitate white phantoms. Oh yeah, and optionally communicate entirely through gestures.

Again, it's kinda hard to get it exactly right, and I don't have much experience in this kind of build, but those are the basics.

I'll have to keep those in mind! I dare you to try the communicating through gestures bit in a game, hahaha. Ironic that you're going with a Tengu here. Played a couple homebrews that had Tengu who used sign language.

Huh! Neat coincidence!

And I am totally going to communicate with gestures. Maybe not ENTIRELY, as dialogue IS necessary and is much less annoying to my teammates. But there'll be a "WELL, WHAT IS IT?" here and there. Might make him follow Sarenrae just so I can "PRAISE THE SUN".

DO IT. I need to make Kenny again. Yes, from South Park. Was a Lankhmar game (dude . . if you haven't heard of that you NEED to check it out) with AD&D 2.5 rules. For some reason the mumbling, crossbow wielding sniper thief was surprisingly badass. Was hell to talk to people with "MMPH" though.

The only problem I can see (from the admittedly small amount of time I spent looking) with using a two-handed sword is that Weapon Finesse doesn't work with them.

It only works on light weapons (and a few exceptions) anyway. Any rogue wanting to get the most out of their damage dice would skip the feat anyway and take something better.

Plus, a good strength score is necessary for this build anyway so it's kind of nil.