Board Thread:Questions and Answers/@comment-3331402-20160425113039/@comment-26322848-20160521030639

The bar beneath the chibi is the character's Trust. You've maybe seen missions that ask you to max a guy's Trust, so in that case, you'd want to do lessons with him until the bar is full.

For the album, from the main home screen, click the map icon in the lower right, then the big blue icon with a picture of an id photo and student handbook. From there, click on the guy whose card you want to take out to pull up his menu screen. There's a yellow button with a shirt, so use that as reference and tap the white button directly underneath it to open his card album. Then, tap the card you want (will have a red triangle in the top right to show it's in the album)  and tap the red button under the card art (will say 取り出す) to take the card out.