The thing we always found funny about Hana's mom is that her husband is basically an older Sakurai in body-type and she has three kids so we doubt she is pent up. It is just that she wants to be like the characters she sees/reads about (implying she likes NTR dramas). She wants the excitement and eventually she will get it.
To Hana's dad: "She is never yours, it is just your turn."