Recommendations

Maybe this?
https://www.mangago.zone/read-manga/that_summer_kim_hyun/

Here ya go. I tagged these as noncliche love triangles :">
- http://www.mangago.zone/read-manga/10th_you_and_i_fell_in_love_with_the_same_person/
- http://www.mangago.zone/read-manga/ao_no_flag/
- http://www.mangago.zone/read-manga/that_summer_kim_hyun/
- http://www.mangago.zone/read-manga/sweet_trap/
- http://www.mangago.zone/read-manga/faded_first_love/
- http://www.mangago.zone/read-manga/pochi_to_tama/

Aquaman
https://www.mangago.zone/read-manga/aquaman/
https://www.mangago.zone/read-manga/ao_no_flag/
https://www.mangago.zone/read-manga/i_want_to_be_the_wall/( still ongoing)
https://www.mangago.zone/read-manga/faded_first_love/
https://www.mangago.zone/read-manga/okaeri_alice/
https://www.mangago.zone/read-manga/triangle_fuuki_mame/
https://www.mangago.zone/read-manga/sweet_trap/

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

Maybe???

This is ends as straight couple with black hair and girl while, the older guy ends up alone

I have recomend but a bit different
Guy x Guy x Girl
But the end game is guy x guy
Title : ao no flag

thank you for all the recommendations! I'll check them out!