What kind of character archetype is this?

What kind of character archetype is this?

Best girl.

it's some kind of Yamada

auto-waifu

Fundere.

( ¯¯¯¯)

But Shiho is best girl

Retard.

Also known as a waste of space and animation budget.

JIIIIIIIIIIIIIIIIII

Okay user, no need to be so mean.
I'm sure your mum thought the same about you, but still kept you.

Proto-Yamada.

jii dess

Burning a stupid user this hard.

Discount Yamada.

Mocho.

you call?

YAMADA

Yamada's imouto.

Who gave her permission to be so cute?

This. Thank god it didn't take seven episodes for her to appear.

Worst character.