Not to mention the appearance and personality of Haibara, you can tell she is easily identical to Irene. Auburn curled hair, a beauty to die for, and a very independent sharp woman who is not afraid to show her wit. But as the manga progresses, Haibara changes. She finds happiness and friendship. She's not just the cold smart girl, but someone who has friends, and likes mysteries, watching football and helping people with love turmoils (ch 705). No more sorrow in Ai.
Irene Adler
As Conan, Sherlock is cold and a total failure when it comes to expressing passion, with the exception of that woman. In one incidence Sherlock demanded a photo of her as the only payment for solving a case, and it remained one of his most prized possessions.
Sad thing is...Irene doesn't end up with Sherlock, she gets married to another man. I think this brings us to lack of emotional expression on the detective's part. In the manga, Haibara showed her disapproval more than once about Conan's secrecy. Sometimes it's too vague to tell who's the girl she's referring to...Ran or herself. (ch 690)
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