What the hell did she mean by "great metabolism"?
context was a bit lost cuz the wording was a bit weird.
Page 6 panels 3 and 4:
"Y-you'll catch a cold, so hurry and cover yourself up"
"ARE YOU IMPLYING THAT MY IMMUNITY IS LOWER THAN THAT OF THE YOUNGER GIRLS!?" (Basically she's sensitive bout her age)
"HOW DID YOU TAKE IT THAT WAY!?" (The "hit box" remark was him asking how she interpreted his previous statement as an insult to her age)
The metabolism thing in Page 7 is accurate, but it's her trying to show him that, despite her age, her body (immunity) isn't weakening.