A Matter of Family was written with intention to expand the storyline of Love Live! and continues the story arch from previous works, of the relationship between Eli Ayase and Umi Sonoda, and it fills the gaps from other members.

This story was written in 9 chapters by 9 members of µ's, one for each chapter of the day. The storyline itself takes a span of almost 1 year in their lives, in chronological order. The purpose of this book is to show the development of the relationship, the involvement other people to their relationship, and the building of a family, and home. It is also a less serious book of the series, but not less important.