This series gets better and better. Episode 5, with it's focus on the relationships of the sisters with each other was really enjoyable.
[spoiler]Kana isn't a total idiot. She managed to trick Chiaki into helping her in buying Haruka a skimpy swimsuit. Then she guilt-tripped Haruka into accepting the <s>swimsuit</s> teeny bikini.
The teruterubozu scene was cute, although I must wonder about Haruka letting Kana tie up Chiaki and dangle her from a pole. I would have thought that she'd object to having a teruterubozu up in an effort to dispel the rain since it would mean she'd have to wear the teeny bikini. Unless she thought that a Chiaki-teruterubozu wouldn't be as effective as a traditional one (who's effectiveness is questionable to begin with). The best part was when Uchida (Chiaki's friend with the long hair) started to worship our cute little teruterubozu and Kana and Yoshino followed suit.
The beach. What do I need to say? Thank goodness for Haruka's friends.
The sisters imagining how it would be if they were alike was funny. Once again, Kana reveals that she isn't the dummy people make her out to be when Chiaki asks why they aren't alike. She responds that it doesn't matter, and if they all were like Chiaki they'd be in trouble. Yeah, it's a side jab to Chiaki, but on occasion Kana has great (but a bit twisted) perception of a situation.