20.21 20.25 [There were many party poppers being pulled to congratulate you in that photo.]
20.25 20.33 [As you may guess due to their gunshot-like sounds, party poppers leave gunshot residue, due to using gunpowder. ]
20.33 20.41 [The residue stuck to your clothes, and then to Nana-san’s clothes when you strangled her.]