Momoi generally has a very bubbly and outgoing personality who sometimes acts flirty, especially with Tetsuya Kuroko. She has a romantic vision of love, falling for Kuroko when he gave her a popsicle stick.

Shintarō Midorima has also commented that Momoi is very passionate about basketball, perhaps even more than players themselves. She becomes very serious and almost sly when analyzing the opponents, often saying that men are just too predictable.