エリカ

Elica is the one and only maid at the research facility. She attends to Sion’s personal needs, and is a cheerful older sister to everyone (as you can tell, she also has a tendency to over-dramatize situation). She also possesses the usual skills of a maid: the ability to do laundry, cook good food, brew excellent tea, clean, martial arts, etc. [Edited from Choux's review.]