User blog comment:B214/Volume 22 spoilers/@comment-78.88.30.241-20170202223230/@comment-30924344-20170202224145

Actually 18 was focused on Irina, 19 was focused on and 20 was focused on Asia. Volume 23 is focused on all three of the church trio girls at once. This is because it is the last volume that will have any focus on them.