Valkyrie Profile/WMG

Lockswell was the one working with Fauxnel.
Rosea and Lies A LOT oh, Lieselotte really WERE innocent. Yea, durr, but IIRC, Fauxnel said that he was only partially responsible for Sir Cennair's death. One person on Gamefaqs actually had the right idea and claimed that it was an assassin. THAT is where I got this theory from! LOCKSWELL WAS THE LEADER OF THE ASSASSIN'S GUILD. THE ROYAL ASSASSIN'S GUILD!!!! He is also a member of the same fallen house Fauxnel was. Wouldn't it be in Lockswell's best interest to restore the lost House and, in a way, avenge his wife and family? To give Cheripha a Noble House to live in? The lives of Rosea and Lieselotte meant nothing to Lockswell, so getting rid of those two would mean that a member of his House becomes Archmagus and BOOM! House slowly gets restored. At least Fauxnel felt guilt for his involvement. Think Lockswell did? No. Plus, who would DARE accuse him? Who would go against the Assassin's Guild? It would also explain why no one would be believe the two girls. To do so would mean the end of their lives. Lockswell didn't get the chance to get rid of Rosea and Lisel because Cheripha deserted soon after. Plus, there's always Fauxnel to 'take over'.

If one of the girls was guilty, it would be Lieselotte.
Notice how she tends to blurt out certain things that sound innocuous at first, but then when you think about it, it's a form of guilt admission or an obvious attempt at provoking someone. She said she was a "failed assassin". Well, that's certainly true in the C Path, but it's also true in the B Path. She committed the same acts in BOTH paths. It's just that in the B path, no one would have considered her until she mentioned "failed assassin" and then Tavern Lore helps put two and two together. See, she mentioned "cantrip". How did she know that? No way the investigators mentioned that detail. Maybe she figured it out on her own? Or maybe she IS guilty, but is betrayed by Fauxnel. In the Japanese guidebook, Liesel and Fauxnel's endings are said to be the only two mentioned and that they "worked together to restore peace to Artolia". No one else's is mentioned. Uh-huh. Too bad it was all in vain seeing as the B ending proved every bit as downer as the C one, except the latter one could be seen as more karmic. Anyway, that tidbit raised a lot of red flags with me, especially since Liesel is the sort would appreciate conniving "ends justifying the means" tactics(something Rosea wouldn't do even if she absolutely had to emply such tactics herself), so she would be a little more forgiving of Fauxnel's actions. Er, maybe. I honestly think Lockswell's involvement is way more likely though.

Rosea is the mortal manifestation of Hrist Valkyrie. Or Soul Jar.
Notice that Silmeria has Alicia, Lenneth has Platina. Who does Hrist have? Well, there is that one woman in VP: Silmeria, but that might have simply been a disguise. In the end of COTP, Silmeria is out of commission and Lenneth is also set to rest. That leaves Hrist. So, Rosea's death is necessary for her to become Hrist. If you take off Rosea's hat and Hrist's helmet, they look frightningly similar. Even the hairstyles match. The personalities are obviously different, but that's true with the other sisters and their mortal forms. However, both Rosea and Hrist have a severe appearance, both usually surpress emotions, and they both are likely to blindly obey who they are most loyal to. Hrist is CERTAINLY like this as she does everything Odin says without question. It's not like Hrist is evil, she's just the most obeidiant of the sisters. Also, because her memories of being Rosea are likely surpressed/erased, it's expected that she'd be the harshest, coldest, and least compassionate/empathic of the sisters. She also would have chopped Lieselotte and Fauxnel to pieces just on principle. Would make an interesting VP sequel, that's for sure. It has to be 26 years at the very least, because that's how old Arngrim is in the original game, and according to Covenant, he's not incarnated on Midgard at that time. Also, it's a young prince (Joshua, who if he's Langrey and Kristoff's contemporary, would be in his early 20s) installed as King at the end of Covenant, and Artolia's king at the start of Lenneth is a middle-aged man, and has a 14-year-old daughter--meaning either A. that young prince had to grow up, B. that's one of his descendants, or C. he was usurped. B is right out as that much time couldn't have passed--it has to be within Gandar's lifetime, and he's 67 in Lenneth--I can't seem to find a concrete number for his age in Covenant. C is possible, but if the king was a usurper, it would render Covenant's plot somewhat moot and besides, someone would have mentioned it--the king seen in Lenneth seems much more like he's been royalty a long time, rather than someone who overthrew a previous king.
 * The biggest problem with this is the timeline. Covenant only takes place 40-50 years or so before the original game (a young Gandar makes an appearance), and there's no evidence that Hrist had been the active valkyrie that recently.
 * I'm not really sure when COTP takes place(I thought it was 10-20 years before Lenneth), but in the end, unless it's the A path that's "canon", Lenneth is out of commission and so is Silmeria. That only leaves Hrist as the Valkyrie. As for Gandar, he didn't look that young to me.
 * The A path is, in fact, canon.
 * Okay, but couldn't Lenneth still be put on a "break" at the end of Path A. Because she was Platina in Artolia. Who would be the Valkyrie when Lenneth was within Platina?
 * I don't think there always has to be a Valkyrie active on Midgard. From how Odin speaks in the first game, it came off to me like there hadn't been a Valkyrie working for a while, and he was calling her up to do one last shopping trip before Ragnarok started.
 * The Valkyries are awakened in a cycle however. So if Lenneth was reawakened, there was a period before the original game where Hrist was the active Valkyrie.