The dynamic between Shawn and the gfs mother was the only good part.
The rest of the movie was just so bleh. Very underwhelming. I guess the Tate scenes were funny too, unintentionally though from what it seemed. Should have just focused a better portion of the movie between that relationship. Loved how the mother could play it off so much easier in front of the family when it was much more obvious how uncomfortable Shawn was about the whole thing. Definitely made me feel uneasy personally as well, and it was only two scenes (the dinner one and when they are on the porch). They definitely had good chemistry going and made it seem like a very believable relationship. Made you question how the relationship started in the first place. That subplot was seriously the only highlight of the film.
Also that prolonged close up shot of the dads penis as hes pissing was very gratuitous to say the least. Not to mention the "ending" that "ties" all of the characters together.