RNGCombo said: The author may be male but his insert character is female, so there's no reason for it to be a mixed bath.
That, plus they are married, and mixed hot-spring/bath is common in Japan.
Ch-click Ch-clickOwuh!?Ch-click Ch-clickGotta be naked for a bath!♡The Hunter Becomes the HuntedNo, stop! Don't shoot meee!!SSZLPI'll get the shots of that area, so you go on in first, Kogasa!Ooorgh!?WHOKSHAPLASH