The art is a 8/10
The plot is 4/10 at best
Ew. Just ew ew ew. ML's whole thinking process is ew. Even putting aside the cousin stuff, the underage dating of a teacher, the plot is still ick. The fact that neither MC or ML sees the pure ick factor of having intercourse under the pretense of "let me rehearse with you pretending you're my non-existent GF who is your twin" is just concerning as all hell. Sure, they're teenagers, but ew.
ML isn't in love, he enjoys being able to manipulate and control the MC. Where is the menhera tag this needs?