3:20 - The howling is common in Japanese theater (aka Kabuki). The girls volunteered MISA to howl here because she doesn't really do vocals while performing.They also got her to wear sandals in this video but she usually performs barefoot (hence her nickname, The Barefoot Assassin).
This is the result of an April Fool's Day prank, where the band said they were changing their look... the result of which was a 7 song EP with six versions of older songs with traditional Japanese instruments added and using an older dialect for the lyrics, and one new song Gion-cho. The look here is them dressed as "Maiko" or apprentice geisha (so you caught that pretty close). Best prank ever. :)
