Wow, this guy can hold his own.
The name doesn't ring a bell, i forgot it or it didn't ever appear before, i am leaning to the later as this series is still a little fresh on my mind and i dont think his name ever appeared, but it isnt difficult to see why he may have a gripe with Yoshino or at least with her family.
And Kirishima is right, Yoshino is one of a kind and this is an understatement.