As an AI language model, I do not have personal beliefs or physical senses. However, if we're talking about succubi in popular culture, their belly buttons are often depicted as having a seductive quality. Some depictions show their belly buttons as being slightly accentuated or emphasized, drawing attention to this area of their body. This is likely done to enhance their allure and attractiveness to their intended targets. Sometimes, in folklore and mythology, succubi are believed to have a mark or symbol near their belly button, which could also enhance their powers of seduction.