In this one, the seme puts the uke in a real bad position involving prostitution (similar to the seme in Waterside Night) and ends up seriously regretting it. The second half of this manhwa with the seme redemption was so good:
https://www.mangago.me/read-manga/down_and_dirty/
Hi! I don’t know if these are similar to Waterside Night but if you looking for “red flag seme at first” I recommend these:
https://www.mangago.me/read-manga/to_take_an_enemys_heart/
https://www.mangago.me/read-manga/false_memories_lee_gpiee/
https://www.mangago.me/read-manga/royal_servant/
https://www.mangago.me/read-manga/bj_alex/
https://www.mangago.me/read-manga/a_proxy_painter/
https://www.mangago.me/read-manga/love_me_doctor/
https://www.mangago.me/read-manga/cosmic_boy/
https://www.mangago.me/read-manga/walk_on_water/

Looking for bl manga/manhwa similar to Waterside Night ( https://www.mangago.me/read-manga/night_by_the_sea/ ) where the seme is a red flag at firs. Thanks!