I believe that by now Ban is already out, it can't be him, in fact this possibility has always been improbable, the personality is opposite, Ban is basically a child in an adult body, he always acts irresponsibly and irresponsibly, Sin is the opposite, refers to lancelot, an adult in a child's body, acts in a mature and serious way, in addition to being very observant, he has already found out about the bird that is watching the group in this chapter, he was the only one in the group who noticed, Ban would never realize this, I didn't want to believe in this possibility, but I believe it practically confirmed that he is Lancelot, he would have met Howzer from the memories of the 7 sins, without the need for a prior encounter. But that's not what I want to talk about, but about a theory I made since the first time I saw sin, and that few people talk about, and it's that sin is Arthur, his true personality, yes, think about it, Nakaba wants to give highlight Arthur, in this sequel so he would be on the good side would be good, maybe this is the real personality and chaos is controlling the real body, the personality is different from the Arthur we know, but 16 years have passed, and Arthur from 16 years ago he was still shaping his character and personality, he wasn't a complete character, his maturation may have generated sin, for me it's the only possibility if it's not lancelot, that would definitely surprise the horse, and it also makes sense to refer to group like kids, as Arthur is 32 now, it would also make sense to see, he would be seeing his fiancée, guinevere, he's the only one who fits that but lancelot.