Really manipulative guy

The beast must die is your call

I've read that one.

https://www.mangago.zone/read-manga/a_link_between_relationships/

https://www.mangago.zone/read-manga/after_killing_you/

https://www.mangago.zone/read-manga/hwang_young_s_misery/

https://www.mangago.zone/read-manga/sura_s_lover/ (more like Yandere)

https://www.mangago.zone/read-manga/can_a_lover_also_be_a_substitute/

https://www.mangago.zone/read-manga/a_link_between_relationships/

https://www.mangago.zone/read-manga/ore_no_sekai_o_hakai_suru_otoko/

https://www.mangago.zone/read-manga/frenzy_train/

https://www.mangago.zone/read-manga/lima_syndrome/

https://www.mangago.zone/read-manga/the_perfect_relationship/

Looks like this one might be like that:
https://www.mangago.zone/read-manga/falling_sheep/