Rentarou is heading to the restroom after a fun game of cards when he bumps into a girl, causing him to drop his cards. The girl is annoyed, but as soon as she looks up, it's a -ZING!!
Girlfriend #23 pauses, but does not drop her surly attitude, even when Rentarou tries to introduce himself. She mumbles to herself that she must have been imagining things as Rentarou kneels down to pick up the cards.
Girlfriend #23's mood shifts, and she frantically picks up several cards, handing them over to Rentarou with a pleasant smile. Rentarou notes that there are still several cards on the floor, but Girlfriend #23 refuses to give a second glance to those. Rentarou is puzzled by this, but eventually realizes that her focus was on the cards with numbers on them. He asks if she likes numbers.
She scoffs at his foolish question. Suu Hifumi doesn't simply like numbers. She's in love with numbers. Rentarou tries to introduce himself again, but Suu doesn't care. She's much friendlier when he gives his class number, though. She doesn't think that's odd; after all, doesn't Rentarou's attitude change when he's around his romantic interest and when he isn't? Rentarou, thinking of the Love God, concedes the point.
He's impressed with Suu, asking if she's good at math. As it turns out, no. In fact, she struggles with basic arithmatic, which she finds dehumanizing to numbers.
When Rentarou asks if she has a favorite number, she says that she hasn't been able to pick one to date. Rentarou can relate to that, since he loves all of his girlfriends so much. Suu compares the different numerals to seeing numbers in different outfits and hairstyles.
The bell rings, and Suu turns to leave. Rentarou asks if they can talk again. Suu coldly brushes him off, saying it's impossible for her to love him.
A few hours later, however, Suu is still thinking about Rentarou. When he calls out to her, he's dressed in a black bodysuit. If Suu can only love numbers, then he'll become numbers. He poses in the shape of a zero, then a one, and so on until number nine. Suu is delighted, but the scene reminds her of the time she attempted to become numbers. She did all the same poses, but she couldn't become the number ten or beyond.
In the present, Rentarou asks Suu to stand next to him as he forms a zero. Together, they've both become ten. And together, they can become the other double-digit numbers, all the way to ninety-nine. On impulse, Suu asks to go out with Rentarou. He accepts, but Suu is worried she's being fickle to her beloved numbers. Rentarou insists that her love for both him and numbers are genuine. He knows how she feels, though: He could never pick between his twenty-two girlfriends.
"That's as many as 2 2s..." Suu sighs in delight as the chapter ends.
