"Mrs. Fall"
The Stage-Three Boss of Mrs. Estacion. She initially confronts and refuses to help Himeka awake from her dream due to her aggression towards Tanabata Furin and Kabuki Mujina. Himeka justifies her actions by saying it's okay since it's a dream, angering Yumemi further.
Fans of Mrs. Estacion aren't sure what species Yumemi is, but it is speculated that she is a dog.