Some fans call her "Zayaku" (座薬, meaning 'suppository'), because her bullets look like them. Many, many jokes have been made about this, often of a crude nature. In addition, some species of plantains carry seeds that are useful for constipation and irritable bowel syndrome, similar to the functions of rectal suppositories.
Reisen's line "I'm just a useless little bunny, only good for my sex appeal," from the doujinshi "Drunkards in Eientei" by Omchicken, has become a popular meme associated with her.
Reisen is usually depicted as helpless, frightened rabbit-girl, always being backstabbed by Tewi and sometimes being used as subject of Eirin's crazy medical experiment or always running on petty errand of lazy Kaguya as her poor servant. Sometimes, this means she is only one sane character in whole Eientei.