WAIT
I’m sorry I only just now found out about Himiko taking the All Might keychain holy shhdkfjhfk why are we not making a bigger deal out of this!! I knew that if the keychain appeared again, the context would be extremely important.
It was symbolic of Ochako hiding away her crush, and also her admiration of Izuku’s All Might -like traits, mainly his self sacrifice. Taking the keychain seems to suggest relieving Ochako of that emulation. Now she’s the one being saved. And again, for this to fully be a positive thing for Ochako, it shouldn’t result in Himiko’s death because Ochako has already dealt with that guilt enough, and it’s time for a real win.
Considering that this moment of Himiko giving Ochako her blood is an act of reciprocating genuine love, there’s a sense of finality. The keychain is gone, and with it her romantic attachment to Izuku, because the void of unrequited love is now being filled by Himiko. Literally.
Like I can’t stress enough how this sudden but understated appearance speaks volumes hidden in plain sight. If this isn’t a smoking gun for putting *that ship to rest, I don’t know what is.