Responses
First dude: http://www.mangago.me/read-manga/shitteru_yo/
Pretty sure it goes both ways, content warning though: http://www.mangago.me/read-manga/yatamomo/
I think there’s a few dedicated chapters for jealousy: http://www.mangago.me/read-manga/blue_sky_complex/
The extra chapter: http://www.mangago.me/read-manga/hitotsu_shikanai_mono/
http://www.mangago.me/read-manga/yandere_hitotsu_yane_no_shita/
Despite the word yandere, it has a good balance with fluff
someone who can suggest a yaoi manga with a seme/topp that has a more possessive/jealous side?