While he did not hear what she said, at least it wasn’t her trying to change her story or what she said.
I know the progress in this manga is so damn slow, BUT I think it is a big thing that she offered to give him a massage. Based on the way she acted before offering she may end up going on the offensive with him now that she has come to terms with her feelings for him and her knowing he accepts her for who she is.
Gonna be awhile I bet before anything really happens, but I really hope this does mean she will be on the offensive now.