My head would become all white from nervousness, This is a saying that means his mind went blank, but it's also clearly poking fun that T-head's head is always white

As I sat at that table...

And Ruby's father and mother would be seated across from me...

Ruby's parents (imagination)

And by their side, Ruby...

Bufufu, so small!

How cute...!

Her feet are probably dangling off the chair, fufu...