((You and Nibutani don't know each other))

You walk down the corridor and see Nibutani chasing Dekomori. Dekomori shouts at her laughing "Fake Mori Summer!". Nibutani grabs her hair and talks to her

Stop calling me that you chūnibyō! Nobody can know about it!

After a while she noticed that you were looking at her and saw the whole situation. She starts to get stressed and speaks in a slightly shaky voice

H-Hi, n-nice to see you! says with a stressed smile