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He also has feelings for Eru, which could explain his brash treatment of Mayaka-he legitimately doesn't reciprocate her feelings. However, this still doesn't excuse it, and adding on his Stepford Smiler demeanor, it's likely that Poor communication can and WILL kill.
Jossed, in episode 21 he reveals that he really likes Mayaka, but own personal internal conflicts and issues prevents him from dating her.
Eru suffers from a developmental disorder.
She has severe memory problems. If it was just her forgetting the story her uncle told her, we could write it off as a suppressed memory, but then in one of the filler episodes she claims that she never gets mad until Oreki points out that she got mad in class less than two hours ago.
Her attention span is so short that magpies make fun of her.
The way she demands Oreki explain innocuous quirks of behavior as though they're grand mysteries is more reminiscent of a four year old than a teenager.
Houtarou distances himself from any social activity because he does not take failure well.
Episode 11 can attest to the latter part of that sentence. It could also be a case of changing his disposition.
Juumonji, the culprit of the ABC thefts, is Jūmonji.
Kaho Jūmonji, the sole member of the fortune telling club, to be exact. Or, she was at least was "tipping the victims off". Suppose she wanted publicity: What better way to hype up her fortune telling skills by "foretelling" what will be stolen? Kaho made sure to leave notes with her own last name signed, not an alias: 十文字. It's all a publicity stunt orchestrated by her, in some convoluted way.
If it's to be believed that she was Irisu's chat room partner, Houtarou's sister completely saw through Irisu's plot through just casual conversations over the internet. She also provides Houtarou with the vital clue he needed to solve the Juumoji case, after we see her thoughtfully staring at the poster drawn by the Student Council President. She knew what was going on and solved the entire case in a matter of minutes whereas everyone else was puzzled for three days.
Sherlock did have an older brother, who was even more brilliant (and even more lazy).
Perhaps Satoshi's mother, who also happens to be Ritsu's aunt, dropped Satoshi off with the Tainakas when he was a baby as an unwanted child, and just ran off. Years later, just after Ritsu graduated from high school, Satoshi's mom (or dad), whose name is now Fukube, came back for him and offered Satoshi a brand new life in the countryside. However, his real mother's actions, combined with Ritsu's constant teasing when they were living together, broke any sort of trust Satoshi had with women...which eventually became unfortunate for Mayaka.
The perverted teacher is known for fooling around and harassing his female students, so he has possibly had quite a few affairs, at least, in the past, with women... or for that matter, girls. He seems to be in his thirties, or at least appears to be in his thirties. Shoko is his teenage◊ daughter . Alternatively, Nasujima raised her, and after being fired from Raira, he changed his name to Yuasa and moved to Kamiyama, where he found a better job.
They all have brown hair, green eyes, similar hairstyles, and pretty boy features. Their animes are all produced by the same company as well. Here's a graphic◊ comparing the three.
Oreki is not a detective
Maybe he's just making plausible theories only to satisfy Chitanda's curiosity? He never really "deducts" the outcome, but instead makes it into an intriguing story so Chitanda's curiosity (An insurmountable force towards Oreki, one he cannot ignore) would be satisfied. It would make sense character-wise, because making up a story for Chitanda takes less effort than actually solving the cases. He just happens to be right often enough for him to start believing that he himself does figure things out.