lackaffe - A German dweeb who thinks they're cool but still can't pass

A German dweeb who thinks they're cool but still can't pass the simplest test.

My friend called me a lackaffe for getting an A on the science test.

My uncle said my dog is a lackaffe for not knowing how to sit.

I texted my brother, 'You’re a lackaffe for not knowing what a triangle is.'