What happened in this part

When Aiko committed suicide Punpun finds her with her undies in her mouth. Did he put them in there? Did she? If so, why?

Heres what I think:

If Punpun:

1: We constantly see Punpun push boundaries with women sexually. With Aiko he does this a lot. Punpun possibly put her panties in her mouth to degrade her, even in her death. He does love Aiko in a twisted way, but he definitely looks at her like an object.

However, he was still definitely upset and terrified when he found her, even bringing her corpse around on his back so I feel like even he wouldn’t do something like that.

2: He put them there to further suffocate her. It’s obvious Punpun wants to kill the both of them so when he finds her he is set on taking is own life. Could it be that he wanted to make sure that she wouldn’t wake up?

We don’t know how long Aiko was hanging there, neither does Punpun. It’d make more sense to check her pulse or even choke her a bit. Why the undies?

If Aiko:

1: Aiko struggles with wetting herself and we see that it completely haunts her. Could she have shoved them in her mouth to degrade herself?

2: Aiko didn’t want Punpun to stop her. Could she have put them in her mouth to muffle any noises? Or to stop herself from possibly surviving?

I’ve seen a lot of people talk about this, let me know what you think!