The Rob and the Mechanical Soldiers are both familiar with Miao Miao, and automatically determine that Miao Miao poses zero threat to Chen Yin, so they were also unprepared for this sudden situation. It wasn't until Miao Miao and Chen Yin were each knocked apart by the other that the Rob and the Mechanical Soldiers helped the two who almost fell.
"I'm sorry, I was too reckless!"
"Sorry, did I hurt you when we collided?"
Even though Miao Miao and Chen Yin hadn't regained their footing, and both were dazed from the sudden collision, their good upbringing made them express their apologies to each other almost simultaneously.
Miao Miao and Chen Yin paused, and as their minds cleared, they realized that the person they bumped into was someone they were somewhat familiar with.
