
What if that butler is violet??? Idk it just makes sense?? I always felt violet had an ulterior motive to be in s4 idol group. We know that he was meeting with someone who had red lines/veins all over his limbs, just like the brother ciel?? Undertaker said that the butler has the Sirius blood group, and guess who had the same blood group in s4!? Violet. Yes. And appreace wise we haven't seen violet without his makeup and stuff, so that can be counted as well. It was also suspicious that he was waiting for original ciel to save him, doesn't makes sense.

I don't think the butler, Lord Polaris, has the Sirius blood type; he'd have the Polaris type, wouldn't he?
It could be possible, though I don't think some things really fit. Polaris is pretty unhinged, like his room implies, and good with knives, something we've never seen out of Violet. Polaris said he was "a butler, even in death." Which implies they were/are dead and revived. As far as we know, Violet is hospitalized, not dead (though anything is possible). However, Violet is also very weak from anemia at the time of the attack on Soma and Agni, which makes it strange that he would be able to take down Agni solo. But maybe he was faking, for some weird reason, or Undertaker beefed him up with something to take Agni down, idk.
But it's the "butler" part that throws me off. Like, this person is someone who has and always was a butler. Violet is not, from what we see. He's a prefect and an art major at a prestigious college; definitely high above butler status. Like "well-off family" status, at least. I honestly don't think it's him.
BUTLER THEORY STUFF
There are other theories that imply the identities of Polaris and the other lords, though. I have a personal theory that he is a revived butler from the previous house's staff, and I've seen a better theory that Polaris is a revived Joker. Appearance-wise, he fits. Joker was technically the butler of the Kelvin manor, when he wasn't the ringmaster. It make sense that Undertaker could save him from the manor fire, since he was there, and maybe he got new prosthetic arms that gave him the strength to take down Agni. We also know he's good with knives, or at least swords. Plus, the end of 169 shows tears pouring out of his eyes, which could symbolize the tear-shaped makeup he wore for shows. God knows what happened to his mind for him to go crazy like that, but we don't know what exactly Undertaker did, so it's possible.
I have theories for the other lords too, hmu

You know, now that I think about it, the Joker theory makes sense. However, I'm really confused that what connection does violet has with the real Ciel. As we saw that when he met him and was kneeling in front of him, it really looked like he was serving him and knew his secret which can imply that he was helping undertaker and Ciel in their scheme. Also Violet was always very secretive and hos past is unknown as well. It would be fun to see who that butler is. But I see why Joker would be Polaris. I'm really looking forward to the next chapters. And please do tell me about the other theories, it was really fun. (≧∀≦)

It's true, Violet is involved with all this. RCiel is 'Lord Sirius', and Violet supplied him with Sirius-type blood during shortages. Violet said he only went along with this whole blood-collecting scheme because the performances of the P4 made his friends so happy, and he didn't want to take that from them. That's all said in ch 125.
Super Long Theory Stuff:
As for the other Lords, I think it has to do with this page in ch 95: http://www.mangago.zone/read-manga/kuroshitsuji/an/manga/kuroshitsuji/v18/c095/pg-6/
The conversation between RCiel and Lord Polaris indicates that Polaris needs blood to stay active, and is thus an evolved Bizarre Doll like RCiel himself. Following this trend, these are all people that were directly killed by OCiel in the pursuit of his revenge. Symbolism aside, they're also all people whose dead bodies Undertaker had access to. Vincent is a no-go, because his body was burned to ash, but Undertaker directly organized Madam Red's burial and was present at the burning of the Kelvin manor where both Joker and Doll died. RCiel is Lord Sirius, and the other three represent the other Lords.
From the Lords' rooms at the music hall, we can infer physical and personality traits. Polaris was a butler, but he is also unhinged and crazy. Joker is technically a butler, as mentioned before. It's a bit of a stretch, but it's also possible Joker underwent some sort of mental breakdown before his death, and it affects him as a reanimated corpse. Since he also lost both of his arms, new, upgraded prosthetics could be the reason why he was strong enough to take Agni alone. Lord Vega's room and behavior indicates two children, probably young girls from the vanity mirrors, who are close enough to talk in unison, or as one. Doll does not have a twin, but she does have an alter-ego as Freckles. So it's possible that that division has manifested in her reanimation much like how Joker's mental state manifested. Finally, Lord Canopus. Canopus's room is very simplistic, but there appears to be a box with what looks like bloody bandages beside the bed. Madam Red was killed via chainsaw to the chest, which leaves a big open wound. Even if it was surgically shut, there's only so much internal damage that can be repaired, so the wound still bleeds. Her room could be simplistic because it's a sanitary place for her to heal or because she isn't the bright and colorful Madam Red anymore. Furthermore, there's what Canopus says to Blavat, "I don't think there's any reason to hesitate any further, am I wrong?" This could be a callback to Jack the Ripper, when Ciel said Madam Red lost because she hesitated in killing him and lost sight of her next move.
If this is true, it makes sense why Joker was the one collecting blood at the Heathfield estate. Mey-Rin and Ran-Mao were disguised as house staff, and Joker was a butler. Madam Red was a doctor, which could mean she's in charge of collecting at the sanatorium where Bard and Lau are. Finny and Snake are going to an orphanage, which makes sense for Doll as well. As for the hotel where Ciel and Sebastian are going, no idea. They'll probably run into Undertaker there or something.
That's all I got for Lord theories

Wow thanks for that. It was soo interesting to read. Actually it all makes sense. I hope you are right!! But if it is then bringing madam red, joker and doll back would be so awesome. I hope it does affect RCiel mentally. I guess we'll have to wait and see. Again thanks for writing all that. (๑•ㅂ•)و✧
*Hoerified* w-what the fuck....