so i ask an ai and it gave me this (i copy and paste ur comment)
The manhwa you’re looking for is almost certainly:
“The Straight Guy’s Guide to Sleeping With Men”
(also known on some sites as “How to Be Straight” or “Straight Man’s Survival Guide”)
Why this matches your memory:
It’s a Korean BL manhwa.
The main character is a shy, awkward “straight” guy who keeps trying to impress girls.
Every chapter is episodic — new characters, new situations.
The running gag is that he tries to get close to girls, but somehow ends up involved with their brothers, cousins, or male friends instead.
Same seme, different “uke” each chapter.
Very comedy‑focused, not serious.
Extremely popular on MRM, often shared under parody/harem tags.
People often describe it exactly the way you did:
“He wants the girls, but ends up with the guys.”
If this isn’t the one, the next closest MRM titles are:
• “The Guy Who Wanted a Girlfriend”
Comedy BL where the protagonist keeps getting derailed by men instead of women.
• “The Straight Man’s Misfortune Series”
Another anthology-style BL parody with a recurring unlucky main character.

read it in mrm its a harem manga about this shy/loser top who would like have a crush on these girls but he'll just ends up sleeping with their brothers instead, every chapter has different ukes but same seme