So is he going to bang his non blood related sister in this trip? At this point he may as well (or be forced to) since he's doing it with every other female aside from the guide goddess (for now). Thanks for the translations.
As attentive as the mother might be, she and the darkelf mistress are fully committed to the father. Nor does the MC show much intrest or inclination twords the females of the general population of the village his family governs.
So it's more then a little exaggerated to say he is going to get frisky with much more then his not sister, the android maids, the android warriors, and the amazons. Even the being known as Mother, shows little intrest in fornicating with the MC. ¯\
(ツ)/¯