Originally posted by Hood
Not necessarily true. The Confidant Booster helps you get the " I feel my bond will grow soon " thing faster, but you won't always get it if you have the booster. Example: If you didn't give them a give, or choose the right answer for friendship points. That alone can stop you from receiving the growing soon. Just because you have a rank booster doesn't mean you'll always get it eachtime. Now for say if you do get the right answers each time. That can get you to it each time without gifts.
Can confirm this. I'm using the booster code while my MC is equipped with the corresponding persona arcanas and my bonds grow faster.
However, the other code that gives you confidant gift key items which help unlock most of their abilities at rank 1 does not work. I have key items like "Sports Watch" and "Morgana's scarf" etc. and I can't use any of the abilities until I hit the rank that unlocks them.