She's not a tsundere, she's just trash.It's probably along the lines of "pitiable". She's too stupid to express herself in any other way other than being an extreme version of a tsundere who never does the dere part. Probably something along the lines of being extremely jealous of people coming close to him, or him leaving her for someone else, so she does the whole "downgrade him until he can't live without me" type of crap.
I thought the same, possessive and abusiveShe reminds me of the girl from https://mangadex.org/title/600f467c-9613-4056-aa21-bb2ecc295b84 - hopefully he stays straight and doesn't whimp out