Y'know, since there isn't any story progression between the witch and Sunao, at this point, Im just gonna head cannon that stupid fake NTR never happened for now. I guess thats the only way I can at least enjoy spending my time readin this series.
That said, I can understand why Lemon doesnt want to follow his plan sheet. I mean, is she supposed to cram all those contents in matter minutes lmao. But, I actually find her throwing it raite away kinda disrespecful. I mean she couldve folded it very small if she wants to hide it in his bag. And wouldnt it be interesting that after the date, she re-reads Sunao's plan sheet throughly and realizes just how much thought and care Sunao put for Kogahara. Maybe she reminisces again about their time, when Sunao really cared for her leading her to regret her actions back then
Another thing I want to add is I like how Sunao in this chapter is reflecting on his plan's flaw instead of jumping on to Lemon and scolding her for not following it