Saeki Emi

Oldest sister and is like a mother to other siblings. Is original worried about her brother with his new behavior as he is writing his new novel. Even finds porn magazines and lube. But after finding out about job tries to support.

Despite supporting him her brother keeps pushing boundary line she is comfortable with. Eventual leading to full on sex and more. She used to be bullied by her brother in younger years doing stuff like playing doctor but he out grew phase. But because of it she turned into a masochist.