I remember reading something like this actually 2 stories.
Hormiya
3D kanojo : http://www.mangago.me/read-manga/3d_kanojo/
Horimiya (I spelt it wrong) : http://www.mangago.me/read-manga/horimiya/
i think you mean the manga Haru x Kiyoヾ(❀╹◡╹)ﾉ~
Tall girl and short guy, Lovely Complex only comes to mind lmfao
But I think it really is Haru x Kiyo since you mentioned "nerdy" and the dude from Lovely Complex is far from nerdy and just an actual dumbass lmao
Thank you guys!! its Haru x Kiyo, I have been looking for a long time so this really helped!
so basically its a shoujo comedy, and the main characters is this extremely tall girl who I think asks out this really short nerdy guy, and there's this dynamic between them that, if I remember correctly, is really funny. not a whole lot to go on I know, but please give me any suggestions :)