I believe it is making a reference to a visual novel known as 'Katawa Shoujo' (it means cripple girls) and the girl is one of the characters from it. I don't get the other part of it though. maybe a RWBY reference.

mercury spoiler it was revealed in rwby this week that mercury black has prosthetic robot legs

Can't wait what did Yang mother said at the end of season 2

raven hasnt shown up yet

but i have a feeling she'll show up and help yang soon

yeh, you got it right