Hello.
I'm looking for a shounen-ai/yaoi with a protective big brother as a main character.
Any suggestions ?

Thank you.

Heaven's Love I think it fits, though I don't quite remember.

It's the Art of Time, it's the Art of Life--
Of the player and the craftsman,
Of the writer of songs, of the creator of love,
Of those who will follow, of those who led,
There's no other way in the world ahead ♥

Acid Town
Mainichi Seiten! series
Brother x Brother
Castle Mango
Uso to Kiss kinda