While attending his grandfather's funeral, thirty-year-old bachelor Daikichi is surprised to discover that his grandfather had an illegitimate child with an unknown mother! The rest of his family, fearing the obligation and embarrassment, want nothing to do with the silent little girl, Rin. Sensing her imminent abandonment and outraged by his complacent family members, Daikichi decides to adopt her himself! ...yet he may have underestimated the difficulty of balancing his work, family, and love life with his role as her guardian.

[Source: MyAnimeList]