recommend

(straight)
https://www.mangago.me/read-manga/i_became_the_younger_sister_of_a_regretful_obsessive_male_lead/
https://www.mangago.me/read-manga/let_s_hide_my_younger_brother_first/

(BL)
https://www.mangago.me/read-manga/the_yandere_top_fatger_is_being_teased/
https://www.mangago.me/read-manga/cozy_obsession/
https://www.mangago.me/read-manga/secretary_jin_s_confinement_diary/
https://www.mangago.me/read-manga/i_became_the_lousy_side_top_official/
https://www.mangago.me/read-manga/yes_it_s_me_the_obsessive_side_top/

in any of these, does the sexuality changes of the mcs of og story?
i don't wanna see when the mcs sexuality changes because of someone's unusual behavior

you mean the ML?
uhhhhh
1. never stated the ml was specifically gay
2. same as 1. they just kinda change what person they obsessed with

3.the original ml of the story he isekaied into is his son. the ml of the manhwa is the original story's mc's dad.
4. he became the mc the ml obsessed with
5. nope
6. nope
7. nope

u can also add
https://www.mangago.me/read-manga/stuck_in_my_sister_s_dating_sim/

and

https://www.mangago.me/read-manga/she_s_the_older_sister_of_the_obsessive_male_lead/

thankyouiuuuu sweetieee (*˘︶˘*).｡.:*♡