This is the mission where Nanami and Itadori were at the movie theater, but this time reii ayashii is with them

Nanami: we typically see curses as if its perfectly natural to. When a curse technique is used it leaves residuals behind. But residuals are much fainter than cursed spirits. So focus your vision and look closely.

Itadori: oh, i can see them! he chuckles

Nanami: of course you can.

the three of them start walking out of the theater

Itadori: couldn't you give me a little more praise or something?

Reii walks up and pats Itadori on the head

Reii: good job.

Itadori: Thanks!

Later they were all standing out side and spotted two curses, Itadori throw his umbrella to get into a fight stance, Reii caught the umbrella.

Nanami killed one of the curses and Itadori killed the other. Reii walks up, still holding the umbrella, she squats and pats the head of curse Itadori killed