Where there is a brother who has a sister complex after their parents passed away and he's a thug/ used to be. (And from what I recall, he could be a manga author now?)

And when the protagonist (sister) falls for the ideal high school president, his sister (who's really pretty) finds that she's liked his brother since high school since she used to be crazy, too.

Some other notable differences: he makes really funny facial expressions. It may be a shoujo and comedy...

Any help would be greatly appreciated!

Aniki wa Tsunayoshi!?

~4400 manga completed
~1700 ongoing...

Very similar plot! But unfortunately no.. the main character gets with the class prez. Thank you though I'll take a peek st this as well.