Although her name does not start with an "I," the "Ai" in "Aiko" signifies an "i" sound in Japanese, indirectly marking her as an "i."
She is a Gemini, quite scatterbrained and prone to misplacing her belongings, but she is also very kind and unbelievably cheerful, even in tough situations. She bears a striking resemblance to Iori Yoshizuki, except for a mole under her left eye. Her close likeness to Iori causes some complications for Seto when she is introduced three-quarters of the way through the manga. Both she and Seto eventually fall in love after they meet. Asou realizes this could pose a problem for Seto's relationship with Iori and decides to move away to preserve their love.
A running gag in the series is the peculiar similarities between the women who come between Ichitaka and Iori. Not only do they all have names starting with "I" (or "AI" in Aiko Asou's case), but they also look remarkably similar. Izumi resembles Iori when her hair is long and looks like Itsuki when it is cut short. Aiko also looks like Iori, almost perfectly, save for a mole on her cheek.
