This is where you get duplicates/additional cards of your girls. This comes in handy should you want to fully transform them or planning to do the "Full Transformation".
There are 4 tabs in the exchange and another which is accessed in the "Daily Mission" tab.
This allows you to exchange Badges for a certain rarity equal to the ones you had. Allowing you to get HR, SR or SSR.
There are 2 (or 3) types in said category, limited and standard. The last one allows you trade a couple of HR or SR to a higher rarity badge.
How to get them
There are few ways to get them, one is by events and the other is by selling/feeding them to another card. Depending on the card a certain number of badges will gained in it.
Note: This are written in red text below the card in question.
This ones are gained when you spend money on Gacha etc. A special limited card (mostly SSR ones of course) are present here.
However you can just exchange them in other things.
Rings are gained via events, both gacha events and raiding a boss. You can exchange them into event cards you gained previously.
Each category has 3 "rarity" of ring, which can be get on a certain boss per event.
Daily Mission Rewards
Daily mission rewards are the "GOOD" labeled seals that are rewarded after completing daily missions (Ex: "Let's part job twice!", "Get 100.000 points in an event!", "Attack 50 times!", etc).
These seals are exchangeable with badges, items, cupid tickets, and even cards (The available cards are the same as the ones that you can pick when reaching level 30 and does not require you to have at least one card of the same kind unlike when using badges) by clicking on the right side tab.