Shiori Sekine/Plot

Chapter 4
She is unofficially introduced by Yuri Nakamura in this chapter.

Chapter 5
Sekine joined up with the rest of the battlefront when they went out to eat in celebration of Otonashi's return.

When both Sekine and Irie heard how Iwasawa wanted to hear about Otonashi's life, they both put their heads down upon realization that Iwasawa may have taken a liking to Otonashi.

At the end of the night she chatted with both Hisako and Sekine about how Hisako wins her Mahjong games, though unlike Irie, is amazed with her ability to cheat every single time. She returns home by getting a ride with Hisako, but not before making a face as she sees Iwasawa and Otonashi together.