https://www.mangago.me/read-manga/kiss_me_liar/
https://www.mangago.me/read-manga/kiss_me_if_you_can/
https://www.mangago.me/read-manga/desire_me_if_you_can/
https://www.mangago.me/read-manga/kiss_the_scumbag/
These are a series they are all omegaverse and they are all really really messed up I have no idea if there is a correct order so I put the links in the order that makes the most sense to me
die in my arms - yandere crazy obsessive uke
love plan- jealous seme (seperation anxiety)
unchanged man - obsessive seme with fucked up morals
bad apple - obsessive psycho seme
shutline - seme is possessive over uke but it's not too toxic (having said that i dont think it's green flag bl either, it's beige flag bl)
naked sword and the tree peony of black - devoted yearner jealous possessive seme
red string quests - seme is quite a bit jealous / possessive over uke but it's normal busts of jealousy not like obsessive obsessive
pieta - seme is actually fucking psycho killer level insane. it's a fucked up juicy toxic story.
hold over you - possessive seme
1995 youth report -seme gets jealous over uke but it's a green flag bl so you'll see casual busts of jealousy and not like OBSESSIVE jealousy.

Recs for Jealous/possessive partner
I don’t mind toxic
BL all forms— show, novel, manhwa/ga/hua