I can confirm that when a character’s affection level reaches 20 (previously was 11), you would get a rare gacha ticket for sure. That means another 20 rare gacha tickets (20 girls x 1)!
Here’s what I did to rotate the girls cleanly:
– For the girl to be rotated out (i.e., have already reached level 20), go to her メモカ setting, equip her weakest card for her main card and take out her sub card. This makes her possibly strongest cards available to others.
– When you rotate a girl in (I just follow the ‘official’ order), go to her メモカ and click おまかせ. It will automatically set the strongest cards for her.
– To check whether you have equipped the strongest cards to overall team, go to メモカ from Main Menu, which list all the cards you have. Set the sorting order to 会計値高い順 すべて (all cards sorted from strongest first). If there is an non-sub-equipped card before a sub-equipped card, check which girl equips that sub-equipped card, and click おまかせ on that girl’s メモカ setting (it should change her sub to use the previously non-sub-equipped card).
P.s., If you’re starting on this game as well, I would appreciate it if you use this referral code: dRxtDTR0RY21x . You’ll get 5 rare diamonds (in-game item) while I get one ^^