That was pretty forced "misunderstanding" right there, the girl could've easily said it was a grandpa, if she didnt know, she would've assume that it was Ren's grandpa or something.
I'm glad this was the chapter I decided to read to see if this manga had improved because that misunderstanding is quite possibly the worst example of idiotic forced drama I've ever seen.
So are they not lovers already because she’s clearly forward enough to get kisses throughout the manga and calling herself the lover and not getting corrected lol. Even if it was to get the boys away....