These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
YMMV: Saiunkoku Monogatari
Fridge Horror: In Episode 3 of the anime Ryuuki mentions that the dose of poison meant for Shuurei was not meant to kill her. Given the most likely culprit for the poisoning, I wondered that if the poisoner's intent wasn't to kill her, then why try and why use poison? Then when I was rewatching the episode when it hit me during a short scene with two ladies of the court gossiping on a Ryuuki sharing Shuurei's bed. Of course the poisoner's intent wasn't to kill her, it was to cause her to have a miscarriage!
"Funny Aneurysm" Moment: Not in the show per se, but in its North American release. The last episode released by Geneon before its collapse, episode 10, is titled "Good Things Come to Those Who Wait". Episodes 11+ would not see the light of day in North America for another full year; many of the show's fans in 2007 doubted it would ever happen.
Kouyuu's constantly getting lost is a Running Gag of the series. In a side story, when he was brought back to the Kou residence by Reishin, he was "persuaded" to stay by being told that the house is haunted and the monster would get angry if he tried to run away. Furniture in the house were then constantly rearranged to reinforce the story and to make sure that the boy could not run away to the point that it completely screwed up his sense of direction. While it is done with good intention, it is still a horrible thing to do to a child.
Ho Yay: Oh so much. Occasionally played for laughs in the early episodes, such as when Shuurei speculates that Ryuuki and Seiran might be in love with each other. Even funnier in later episodes when it is revealed that Ryuuki and Seiran are brothers.
Real Women Never Wear Dresses: Beautifully averted. Shuurei is able to be successful in a male-dominated society through brains and hard work, and she's allowed to be as feminine as she wants while she's doing it, dammit.