bl where someone who wasn't an omega initially becomes one. thank you in advance. :)

omg i remember reading one about a beta that worked as a secretary for his boss an alpha, he had an unrequired crush on him that actually had an omega lover, and later in the story he turns into an omega. I dont remember the title sorry if i remember i will tell u

Here's one, I don't know if you have read it or not:
1. https://www.mangago.me/read-manga/kiss_me_liar/
2. https://www.mangago.me/read-manga/kiss_me_liar_special_episodes_ssfujoshi/

The uke originally a beta, then becomes an omega because of the seme alpha's pheromones.

Here's another common/famous one:
1. https://www.mangago.me/read-manga/love_is_an_illusion/

The uke thought he's an alpha throughout his life, met the seme who's a dominant alpha, and becomes an omega in one night.

Here's another one lol:
1. https://www.mangago.me/read-manga/struggle_1/

I don't remember, but the uke is a beta originally, he becomes an omega and got pregnant with the alpha's child when the uke found out he's an omega.

Have you read these?
https://www.mangago.me/read-manga/evenly_matched_love/
https://www.mangago.me/read-manga/kami_sama_wa_chotto_dake_ijiwaru/
https://www.mangago.me/read-manga/peach_musk/
https://www.mangago.me/read-manga/sensei_no_kenkyu/
https://www.mangago.me/read-manga/paradigm_shift/
https://www.mangago.me/read-manga/kyou_kara_omega_ni_narimashita/
https://www.mangago.me/read-manga/takane_no_hana_wa_chirasaretai/

- https://www.mangago.me/read-manga/willow_love_story/
- https://www.mangago.me/read-manga/fatal_attraction/
- https://www.mangago.me/read-manga/omega_complex_1/
- https://www.mangago.me/read-manga/butler_nabit/
- https://www.mangago.me/read-manga/omega_bus_stop/
- https://www.mangago.me/read-manga/eiffel_tower_at_sunset/
- https://www.mangago.me/read-manga/beta_count_so_has_changed/
- https://www.mangago.me/read-manga/boku_no_omega_yo_samenaide/
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YES I FOUND IT thanks to the other replies, the one I was saying was "butler"

Wow wow wow you guys DELIVERED, thank you all so much for your help. Imma go binge these XD

https://www.mangago.me/read-manga/eiffel_tower_at_sunset/ I'm reading this rn, they are a bit older & the MC presents as an Omega at 37 y.o.