Thanks for the chapter!
In the LN it mentions that Honoka's swimsuit was designed more for appearance than practicality which is why the wardrobe malfunction happened when she went in the water. Also, that Tatsuya's body is not only covered in scars from cuts but burns, acid, puncture wounds, etc. as well to point where couldn't place a hand anywhere on his torso without touching at least two scars. Considering his healing ability and how the sight of his scars would distress Miyuki over how he must have been terribly injured I'm surprised he went with keeping them as signs of needing to improve his abilities instead of healing them.