[This private doesn't even know of Sephiroth's particular rank yet, either. Still, correcting the man would only diffuse some of the authority Sephiroth has managed to exert over the situation. Let the man figure it out for himself, later.]

I strongly suggest that you get back down below and demonstrate some better self-restraint for the remainder of the flight. Lest I feel inclined to report this incident to your SO once we arrive.

[He's got a strong hunch that Rukia is most likely peering around him even if he wishes she wouldn't but there isn't anything to be done about that either. Sephiroth keeps his gaze on the troublesome private until he's slipped well out of sight.]