It'd been two days and Tomonori was still heartbroken over what he had seen at the park.

He was at that same park, looking melancholic, when all of a sudden he heard a voice behind him:
"Um, hey... sumo guy."

When Tomonori turned around to see who had said it, there he was: the cat Harumi was dating, or rather the cat he thought
Harumi was dating.

"G-go away!" He shouted at him. "You took my dear Harumi away from me and didn't even bother explaining it away!"

The cat said "Whoa, hold it there! you LIKE my cousin?"
"No, no, forget I said anything, you can have her all for yourse-" Tomonori suddenly realized what the cat had said. "c-cousin?"

Kajinosuke was right, turned out the cat Harumi was with was just her cousin.
"I think we haven't been introduced yet: I'm Yoshimasa Yokozawa (横沢 義政), you had seen us together, didn't you? AAAAAND you thought we were a couple!" Yoshimasa began to laugh.
Tomonori was quick to shut him, and explained to him that even though Tomonori was in love with Harumi, she didn't know it yet, and that he was going to tell her when he had the chance.

Just when he thought it was all lost, Tomonori's chance of asking Harumi out had resurfaced.
In the end, Tomonori had made a new friend, a friend whose lips were sealed.