The feminine polite sentence-final わ plus よ/ね is characteristic of refined feminine speech — older, literary, or 'お嬢様' (young-lady) register rather than neutral modern conversation. 蒸発する literally 'to evaporate,' but used as set idiomatic slang for a person suddenly vanishing from their life (skipping debts, leaving home). ~そうです attached to a plain-form clause is hearsay: 'I hear that / they say.' ご両親 is the honorific 'your parents.'