I'm a bit confused which character you are talking about. The only characters that has 40+ lust are the step-dad and step-bro. Other ones have maximum lust in much lower value.
oh I'm not talking about lust. I'm talking about the ring.
I'm even more confused now. Ring mechanic doesn't involve any large number like 40+.
Oh my bad. You're probably talking about the magic mini game: Meditate -> Convince -> Meditate -> Persuade to reach 45 point.
