Frank was a little confused by her saying "burden," about something so simple.
"I didn't mean it would be a burden, but... well, I didn't mean to offend you. But I guess you walk in the garden by yourself too... I should have thought of that."
He was starting to think Blythe worried far too much about being a "burden," but he wasn't sure how to assure her that she really was not a burder at Asgard. If her healing people such as Ryuzaki wasn't enough to show that, what would be?