Ankh does let go of the back of Eiji's hair to help pull her up, firmly gripping her hand even has he keeps pumping Eiji. He's not worried about him falling with how they are sitting and not standing, but it's worth splitting his attention to make sure Hina doesn't slip.

He does buck under Eiji's hand, before turning to Hina with a smirk. "You should join us." He has the look of the hawk that swallowed the mouse and was eyeing a second one to swoop in on, paying no mind at all to Hina's yelling yet.