Senra follows Louise on the shop and then appearance of cute girl in sexy armor get up cheerily starts take his measurements. He felt growing taunt and stiff on image of the girl being nude and she had some suggestive flirting and measurement taking (how size of his groin department matters?), but Louise's freezing gaze worked as lust killer for sure so he did not reach anywhere but to half-mast. Goosegumps coming both being nude, tickling measurement and the chilling gaze from Louise. So he obeyed what the adventurer shop girl told him to do and he did so in solemn silence.