Right. No way he doesn't have a boner and she doesn't feel it.
A bit of a self own on my part, but you all must have huge dicks or something, or are 3d space impaired. Cause with the way she sits on him and the way he sits on, he would need to have a huge dick, growing straight not curved, somehow pitching him a tent of some sorts, and her pushing her ass towards his crotch to feel it, while him not doing anything to "correct the situation" by laying the log sideways or something.
In most scenarios thou the D even if grown would probably go one of the sides, or even the middle, without pitching to big of a tent, and with her not pushing her ass as far into his crotch as possible, she probably wouldn't feel a thing. Especially if the "swimming pool protection" works and stops him from getting a boner in the first place. At least 20+ years ago I recall myself and bros coming to conclusion we have some unconscious protection working, cause none of us was getting boners on swimming lessons even with girls on the other side of the pool, while getting them in class - stupid world laws abiding - exactly the moment we are called to the blackboard was quite common

. Like brain knew normal clothes would help hide it, but swimming wear not really.